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-rw-r--r--lib/impure/db_mysql.nim424
-rw-r--r--lib/impure/db_odbc.nim532
-rw-r--r--lib/impure/db_postgres.nim590
-rw-r--r--lib/impure/db_sqlite.nim950
-rw-r--r--lib/impure/nre.nim178
-rw-r--r--lib/impure/nre/private/util.nim2
-rw-r--r--lib/impure/rdstdin.nim21
-rw-r--r--lib/impure/re.nim121
8 files changed, 190 insertions, 2628 deletions
diff --git a/lib/impure/db_mysql.nim b/lib/impure/db_mysql.nim
deleted file mode 100644
index 242ea1b0d..000000000
--- a/lib/impure/db_mysql.nim
+++ /dev/null
@@ -1,424 +0,0 @@
-#
-#
-#            Nim's Runtime Library
-#        (c) Copyright 2015 Andreas Rumpf
-#
-#    See the file "copying.txt", included in this
-#    distribution, for details about the copyright.
-#
-
-## A higher level `mySQL`:idx: database wrapper. The same interface is
-## implemented for other databases too.
-##
-## See also: `db_odbc <db_odbc.html>`_, `db_sqlite <db_sqlite.html>`_,
-## `db_postgres <db_postgres.html>`_.
-##
-## Parameter substitution
-## ======================
-##
-## All `db_*` modules support the same form of parameter substitution.
-## That is, using the `?` (question mark) to signify the place where a
-## value should be placed. For example:
-##
-## .. code-block:: Nim
-##     sql"INSERT INTO myTable (colA, colB, colC) VALUES (?, ?, ?)"
-##
-##
-## Examples
-## ========
-##
-## Opening a connection to a database
-## ----------------------------------
-##
-## .. code-block:: Nim
-##     import std/db_mysql
-##     let db = open("localhost", "user", "password", "dbname")
-##     db.close()
-##
-## Creating a table
-## ----------------
-##
-## .. code-block:: Nim
-##      db.exec(sql"DROP TABLE IF EXISTS myTable")
-##      db.exec(sql("""CREATE TABLE myTable (
-##                       id integer,
-##                       name varchar(50) not null)"""))
-##
-## Inserting data
-## --------------
-##
-## .. code-block:: Nim
-##     db.exec(sql"INSERT INTO myTable (id, name) VALUES (0, ?)",
-##             "Dominik")
-##
-## Larger example
-## --------------
-##
-## .. code-block:: Nim
-##
-##  import std/[db_mysql, math]
-##
-##  let theDb = open("localhost", "nim", "nim", "test")
-##
-##  theDb.exec(sql"Drop table if exists myTestTbl")
-##  theDb.exec(sql("create table myTestTbl (" &
-##      " Id    INT(11)     NOT NULL AUTO_INCREMENT PRIMARY KEY, " &
-##      " Name  VARCHAR(50) NOT NULL, " &
-##      " i     INT(11), " &
-##      " f     DECIMAL(18,10))"))
-##
-##  theDb.exec(sql"START TRANSACTION")
-##  for i in 1..1000:
-##    theDb.exec(sql"INSERT INTO myTestTbl (name,i,f) VALUES (?,?,?)",
-##          "Item#" & $i, i, sqrt(i.float))
-##  theDb.exec(sql"COMMIT")
-##
-##  for x in theDb.fastRows(sql"select * from myTestTbl"):
-##    echo x
-##
-##  let id = theDb.tryInsertId(sql"INSERT INTO myTestTbl (name,i,f) VALUES (?,?,?)",
-##          "Item#1001", 1001, sqrt(1001.0))
-##  echo "Inserted item: ", theDb.getValue(sql"SELECT name FROM myTestTbl WHERE id=?", id)
-##
-##  theDb.close()
-
-
-import strutils, mysql
-
-import db_common
-export db_common
-
-import std/private/since
-
-type
-  DbConn* = distinct PMySQL ## encapsulates a database connection
-  Row* = seq[string]   ## a row of a dataset. NULL database values will be
-                       ## converted to nil.
-  InstantRow* = object ## a handle that can be used to get a row's
-                       ## column text on demand
-    row: cstringArray
-    len: int
-
-proc dbError*(db: DbConn) {.noreturn.} =
-  ## raises a DbError exception.
-  var e: ref DbError
-  new(e)
-  e.msg = $mysql.error(PMySQL db)
-  raise e
-
-when false:
-  proc dbQueryOpt*(db: DbConn, query: string, args: varargs[string, `$`]) =
-    var stmt = mysql_stmt_init(db)
-    if stmt == nil: dbError(db)
-    if mysql_stmt_prepare(stmt, query, len(query)) != 0:
-      dbError(db)
-    var
-      binding: seq[MYSQL_BIND]
-    discard mysql_stmt_close(stmt)
-
-proc dbQuote*(s: string): string =
-  ## DB quotes the string.
-  result = newStringOfCap(s.len + 2)
-  result.add "'"
-  for c in items(s):
-    # see https://cheatsheetseries.owasp.org/cheatsheets/SQL_Injection_Prevention_Cheat_Sheet.html#mysql-escaping
-    case c
-    of '\0': result.add "\\0"
-    of '\b': result.add "\\b"
-    of '\t': result.add "\\t"
-    of '\l': result.add "\\n"
-    of '\r': result.add "\\r"
-    of '\x1a': result.add "\\Z"
-    of '"': result.add "\\\""
-    of '\'': result.add "\\'"
-    of '\\': result.add "\\\\"
-    of '_': result.add "\\_"
-    else: result.add c
-  add(result, '\'')
-
-proc dbFormat(formatstr: SqlQuery, args: varargs[string]): string =
-  result = ""
-  var a = 0
-  for c in items(string(formatstr)):
-    if c == '?':
-      add(result, dbQuote(args[a]))
-      inc(a)
-    else:
-      add(result, c)
-
-proc tryExec*(db: DbConn, query: SqlQuery, args: varargs[string, `$`]): bool {.
-  tags: [ReadDbEffect, WriteDbEffect].} =
-  ## tries to execute the query and returns true if successful, false otherwise.
-  var q = dbFormat(query, args)
-  return mysql.realQuery(PMySQL db, q, q.len) == 0'i32
-
-proc rawExec(db: DbConn, query: SqlQuery, args: varargs[string, `$`]) =
-  var q = dbFormat(query, args)
-  if mysql.realQuery(PMySQL db, q, q.len) != 0'i32: dbError(db)
-
-proc exec*(db: DbConn, query: SqlQuery, args: varargs[string, `$`]) {.
-  tags: [ReadDbEffect, WriteDbEffect].} =
-  ## executes the query and raises EDB if not successful.
-  var q = dbFormat(query, args)
-  if mysql.realQuery(PMySQL db, q, q.len) != 0'i32: dbError(db)
-
-proc newRow(L: int): Row =
-  newSeq(result, L)
-  for i in 0..L-1: result[i] = ""
-
-proc properFreeResult(sqlres: mysql.PRES, row: cstringArray) =
-  if row != nil:
-    while mysql.fetchRow(sqlres) != nil: discard
-  mysql.freeResult(sqlres)
-
-iterator fastRows*(db: DbConn, query: SqlQuery,
-                   args: varargs[string, `$`]): Row {.tags: [ReadDbEffect].} =
-  ## executes the query and iterates over the result dataset.
-  ##
-  ## This is very fast, but potentially dangerous.  Use this iterator only
-  ## if you require **ALL** the rows.
-  ##
-  ## Breaking the fastRows() iterator during a loop will cause the next
-  ## database query to raise an [EDb] exception `Commands out of sync`.
-  rawExec(db, query, args)
-  var sqlres = mysql.useResult(PMySQL db)
-  if sqlres != nil:
-    var
-      L = int(mysql.numFields(sqlres))
-      row: cstringArray
-      result: Row
-      backup: Row
-    newSeq(result, L)
-    while true:
-      row = mysql.fetchRow(sqlres)
-      if row == nil: break
-      for i in 0..L-1:
-        setLen(result[i], 0)
-        result[i].add row[i]
-      yield result
-    properFreeResult(sqlres, row)
-
-iterator instantRows*(db: DbConn, query: SqlQuery,
-                      args: varargs[string, `$`]): InstantRow
-                      {.tags: [ReadDbEffect].} =
-  ## Same as fastRows but returns a handle that can be used to get column text
-  ## on demand using []. Returned handle is valid only within the iterator body.
-  rawExec(db, query, args)
-  var sqlres = mysql.useResult(PMySQL db)
-  if sqlres != nil:
-    let L = int(mysql.numFields(sqlres))
-    var row: cstringArray
-    while true:
-      row = mysql.fetchRow(sqlres)
-      if row == nil: break
-      yield InstantRow(row: row, len: L)
-    properFreeResult(sqlres, row)
-
-proc setTypeName(t: var DbType; f: PFIELD) =
-  t.name = $f.name
-  t.maxReprLen = Natural(f.max_length)
-  if (NOT_NULL_FLAG and f.flags) != 0: t.notNull = true
-  case f.ftype
-  of TYPE_DECIMAL:
-    t.kind = dbDecimal
-  of TYPE_TINY:
-    t.kind = dbInt
-    t.size = 1
-  of TYPE_SHORT:
-    t.kind = dbInt
-    t.size = 2
-  of TYPE_LONG:
-    t.kind = dbInt
-    t.size = 4
-  of TYPE_FLOAT:
-    t.kind = dbFloat
-    t.size = 4
-  of TYPE_DOUBLE:
-    t.kind = dbFloat
-    t.size = 8
-  of TYPE_NULL:
-    t.kind = dbNull
-  of TYPE_TIMESTAMP:
-    t.kind = dbTimestamp
-  of TYPE_LONGLONG:
-    t.kind = dbInt
-    t.size = 8
-  of TYPE_INT24:
-    t.kind = dbInt
-    t.size = 3
-  of TYPE_DATE:
-    t.kind = dbDate
-  of TYPE_TIME:
-    t.kind = dbTime
-  of TYPE_DATETIME:
-    t.kind = dbDatetime
-  of TYPE_YEAR:
-    t.kind = dbDate
-  of TYPE_NEWDATE:
-    t.kind = dbDate
-  of TYPE_VARCHAR, TYPE_VAR_STRING, TYPE_STRING:
-    t.kind = dbVarchar
-  of TYPE_BIT:
-    t.kind = dbBit
-  of TYPE_NEWDECIMAL:
-    t.kind = dbDecimal
-  of TYPE_ENUM: t.kind = dbEnum
-  of TYPE_SET: t.kind = dbSet
-  of TYPE_TINY_BLOB, TYPE_MEDIUM_BLOB, TYPE_LONG_BLOB,
-     TYPE_BLOB: t.kind = dbBlob
-  of TYPE_GEOMETRY:
-    t.kind = dbGeometry
-
-proc setColumnInfo(columns: var DbColumns; res: PRES; L: int) =
-  setLen(columns, L)
-  for i in 0..<L:
-    let fp = mysql.fetch_field_direct(res, cint(i))
-    setTypeName(columns[i].typ, fp)
-    columns[i].name = $fp.name
-    columns[i].tableName = $fp.table
-    columns[i].primaryKey = (fp.flags and PRI_KEY_FLAG) != 0
-    #columns[i].foreignKey = there is no such thing in mysql
-
-iterator instantRows*(db: DbConn; columns: var DbColumns; query: SqlQuery;
-                      args: varargs[string, `$`]): InstantRow =
-  ## Same as fastRows but returns a handle that can be used to get column text
-  ## on demand using []. Returned handle is valid only within the iterator body.
-  rawExec(db, query, args)
-  var sqlres = mysql.useResult(PMySQL db)
-  if sqlres != nil:
-    let L = int(mysql.numFields(sqlres))
-    setColumnInfo(columns, sqlres, L)
-    var row: cstringArray
-    while true:
-      row = mysql.fetchRow(sqlres)
-      if row == nil: break
-      yield InstantRow(row: row, len: L)
-    properFreeResult(sqlres, row)
-
-
-proc `[]`*(row: InstantRow, col: int): string {.inline.} =
-  ## Returns text for given column of the row.
-  $row.row[col]
-
-proc unsafeColumnAt*(row: InstantRow, index: int): cstring {.inline.} =
-  ## Return cstring of given column of the row
-  row.row[index]
-
-proc len*(row: InstantRow): int {.inline.} =
-  ## Returns number of columns in the row.
-  row.len
-
-proc getRow*(db: DbConn, query: SqlQuery,
-             args: varargs[string, `$`]): Row {.tags: [ReadDbEffect].} =
-  ## Retrieves a single row. If the query doesn't return any rows, this proc
-  ## will return a Row with empty strings for each column.
-  rawExec(db, query, args)
-  var sqlres = mysql.useResult(PMySQL db)
-  if sqlres != nil:
-    var L = int(mysql.numFields(sqlres))
-    result = newRow(L)
-    var row = mysql.fetchRow(sqlres)
-    if row != nil:
-      for i in 0..L-1:
-        setLen(result[i], 0)
-        add(result[i], row[i])
-    properFreeResult(sqlres, row)
-
-proc getAllRows*(db: DbConn, query: SqlQuery,
-                 args: varargs[string, `$`]): seq[Row] {.tags: [ReadDbEffect].} =
-  ## executes the query and returns the whole result dataset.
-  result = @[]
-  rawExec(db, query, args)
-  var sqlres = mysql.useResult(PMySQL db)
-  if sqlres != nil:
-    var L = int(mysql.numFields(sqlres))
-    var row: cstringArray
-    var j = 0
-    while true:
-      row = mysql.fetchRow(sqlres)
-      if row == nil: break
-      setLen(result, j+1)
-      newSeq(result[j], L)
-      for i in 0..L-1:
-        result[j][i] = $row[i]
-      inc(j)
-    mysql.freeResult(sqlres)
-
-iterator rows*(db: DbConn, query: SqlQuery,
-               args: varargs[string, `$`]): Row {.tags: [ReadDbEffect].} =
-  ## same as `fastRows`, but slower and safe.
-  for r in items(getAllRows(db, query, args)): yield r
-
-proc getValue*(db: DbConn, query: SqlQuery,
-               args: varargs[string, `$`]): string {.tags: [ReadDbEffect].} =
-  ## executes the query and returns the first column of the first row of the
-  ## result dataset. Returns "" if the dataset contains no rows or the database
-  ## value is NULL.
-  result = getRow(db, query, args)[0]
-
-proc tryInsertId*(db: DbConn, query: SqlQuery,
-                  args: varargs[string, `$`]): int64 {.tags: [WriteDbEffect].} =
-  ## executes the query (typically "INSERT") and returns the
-  ## generated ID for the row or -1 in case of an error.
-  var q = dbFormat(query, args)
-  if mysql.realQuery(PMySQL db, q, q.len) != 0'i32:
-    result = -1'i64
-  else:
-    result = mysql.insertId(PMySQL db)
-
-proc insertId*(db: DbConn, query: SqlQuery,
-               args: varargs[string, `$`]): int64 {.tags: [WriteDbEffect].} =
-  ## executes the query (typically "INSERT") and returns the
-  ## generated ID for the row.
-  result = tryInsertID(db, query, args)
-  if result < 0: dbError(db)
-
-proc tryInsert*(db: DbConn, query: SqlQuery, pkName: string,
-                args: varargs[string, `$`]): int64
-               {.tags: [WriteDbEffect], raises: [], since: (1, 3).} =
-  ## same as tryInsertID
-  tryInsertID(db, query, args)
-
-proc insert*(db: DbConn, query: SqlQuery, pkName: string,
-             args: varargs[string, `$`]): int64
-            {.tags: [WriteDbEffect], since: (1, 3).} =
-  ## same as insertId
-  result = tryInsert(db, query,pkName, args)
-  if result < 0: dbError(db)
-
-proc execAffectedRows*(db: DbConn, query: SqlQuery,
-                       args: varargs[string, `$`]): int64 {.
-                       tags: [ReadDbEffect, WriteDbEffect].} =
-  ## runs the query (typically "UPDATE") and returns the
-  ## number of affected rows
-  rawExec(db, query, args)
-  result = mysql.affectedRows(PMySQL db)
-
-proc close*(db: DbConn) {.tags: [DbEffect].} =
-  ## closes the database connection.
-  if PMySQL(db) != nil: mysql.close(PMySQL db)
-
-proc open*(connection, user, password, database: string): DbConn {.
-  tags: [DbEffect].} =
-  ## opens a database connection. Raises `EDb` if the connection could not
-  ## be established.
-  var res = mysql.init(nil)
-  if res == nil: dbError("could not open database connection")
-  let
-    colonPos = connection.find(':')
-    host = if colonPos < 0: connection
-           else: substr(connection, 0, colonPos-1)
-    port: int32 = if colonPos < 0: 0'i32
-                  else: substr(connection, colonPos+1).parseInt.int32
-  if mysql.realConnect(res, host, user, password, database,
-                       port, nil, 0) == nil:
-    var errmsg = $mysql.error(res)
-    mysql.close(res)
-    dbError(errmsg)
-  result = DbConn(res)
-
-proc setEncoding*(connection: DbConn, encoding: string): bool {.
-  tags: [DbEffect].} =
-  ## sets the encoding of a database connection, returns true for
-  ## success, false for failure.
-  result = mysql.set_character_set(PMySQL connection, encoding) == 0
diff --git a/lib/impure/db_odbc.nim b/lib/impure/db_odbc.nim
deleted file mode 100644
index 1e4032b34..000000000
--- a/lib/impure/db_odbc.nim
+++ /dev/null
@@ -1,532 +0,0 @@
-#
-#
-#            Nim's Runtime Library
-#        (c) Copyright 2015 Nim Contributors
-#
-#    See the file "copying.txt", included in this
-#    distribution, for details about the copyright.
-#
-
-## A higher level `ODBC` database wrapper.
-##
-## This is the same interface that is implemented for other databases.
-##
-## This has NOT yet been (extensively) tested against ODBC drivers for
-## Teradata, Oracle, Sybase, MSSqlvSvr, et. al.  databases.
-##
-## Currently all queries are ANSI calls, not Unicode.
-##
-## See also: `db_postgres <db_postgres.html>`_, `db_sqlite <db_sqlite.html>`_,
-## `db_mysql <db_mysql.html>`_.
-##
-## Parameter substitution
-## ======================
-##
-## All `db_*` modules support the same form of parameter substitution.
-## That is, using the `?` (question mark) to signify the place where a
-## value should be placed. For example:
-##
-## .. code-block:: Nim
-##     sql"INSERT INTO myTable (colA, colB, colC) VALUES (?, ?, ?)"
-##
-##
-## Examples
-## ========
-##
-## Opening a connection to a database
-## ----------------------------------
-##
-## .. code-block:: Nim
-##     import std/db_odbc
-##     var db = open("localhost", "user", "password", "dbname")
-##     db.close()
-##
-## Creating a table
-## ----------------
-##
-## .. code-block:: Nim
-##      db.exec(sql"DROP TABLE IF EXISTS myTable")
-##      db.exec(sql("""CREATE TABLE myTable (
-##                       id integer,
-##                       name varchar(50) not null)"""))
-##
-## Inserting data
-## --------------
-##
-## .. code-block:: Nim
-##     db.exec(sql"INSERT INTO myTable (id, name) VALUES (0, ?)",
-##             "Andreas")
-##
-## Large example
-## -------------
-##
-## .. code-block:: Nim
-##
-##  import std/[db_odbc, math]
-##
-##  var theDb = open("localhost", "nim", "nim", "test")
-##
-##  theDb.exec(sql"Drop table if exists myTestTbl")
-##  theDb.exec(sql("create table myTestTbl (" &
-##      " Id    INT(11)     NOT NULL AUTO_INCREMENT PRIMARY KEY, " &
-##      " Name  VARCHAR(50) NOT NULL, " &
-##      " i     INT(11), " &
-##      " f     DECIMAL(18,10))"))
-##
-##  theDb.exec(sql"START TRANSACTION")
-##  for i in 1..1000:
-##    theDb.exec(sql"INSERT INTO myTestTbl (name,i,f) VALUES (?,?,?)",
-##          "Item#" & $i, i, sqrt(i.float))
-##  theDb.exec(sql"COMMIT")
-##
-##  for x in theDb.fastRows(sql"select * from myTestTbl"):
-##    echo x
-##
-##  let id = theDb.tryInsertId(sql"INSERT INTO myTestTbl (name,i,f) VALUES (?,?,?)",
-##          "Item#1001", 1001, sqrt(1001.0))
-##  echo "Inserted item: ", theDb.getValue(sql"SELECT name FROM myTestTbl WHERE id=?", id)
-##
-##  theDb.close()
-
-import strutils, odbcsql
-import db_common
-export db_common
-
-import std/private/since
-
-type
-  OdbcConnTyp = tuple[hDb: SqlHDBC, env: SqlHEnv, stmt: SqlHStmt]
-  DbConn* = OdbcConnTyp    ## encapsulates a database connection
-  Row* = seq[string]   ## a row of a dataset. NULL database values will be
-                       ## converted to nil.
-  InstantRow* = tuple[row: seq[string], len: int]  ## a handle that can be
-                                                    ## used to get a row's
-                                                    ## column text on demand
-
-var
-  buf: array[0..4096, char]
-
-proc properFreeResult(hType: int, sqlres: var SqlHandle) {.
-          tags: [WriteDbEffect], raises: [].} =
-  try:
-    discard SQLFreeHandle(hType.TSqlSmallInt, sqlres)
-    sqlres = nil
-  except: discard
-
-proc getErrInfo(db: var DbConn): tuple[res: int, ss, ne, msg: string] {.
-          tags: [ReadDbEffect], raises: [].} =
-  ## Returns ODBC error information
-  var
-    sqlState: array[0..512, char]
-    nativeErr: array[0..512, char]
-    errMsg: array[0..512, char]
-    retSz: TSqlSmallInt = 0
-    res: TSqlSmallInt = 0
-  try:
-    sqlState[0] = '\0'
-    nativeErr[0] = '\0'
-    errMsg[0] = '\0'
-    res = SQLErr(db.env, db.hDb, db.stmt,
-              cast[PSQLCHAR](sqlState.addr),
-              cast[PSQLCHAR](nativeErr.addr),
-              cast[PSQLCHAR](errMsg.addr),
-              511.TSqlSmallInt, retSz.addr)
-  except:
-    discard
-  return (res.int, $(addr sqlState), $(addr nativeErr), $(addr errMsg))
-
-proc dbError*(db: var DbConn) {.
-          tags: [ReadDbEffect, WriteDbEffect], raises: [DbError] .} =
-  ## Raises an `[DbError]` exception with ODBC error information
-  var
-    e: ref DbError
-    ss, ne, msg: string = ""
-    isAnError = false
-    res: int = 0
-    prevSs = ""
-  while true:
-    prevSs = ss
-    (res, ss, ne, msg) = db.getErrInfo()
-    if prevSs == ss:
-      break
-    # sqlState of 00000 is not an error
-    elif ss == "00000":
-      break
-    elif ss == "01000":
-      echo "\nWarning: ", ss, " ", msg
-      continue
-    else:
-      isAnError = true
-      echo "\nError: ", ss, " ", msg
-  if isAnError:
-    new(e)
-    e.msg = "ODBC Error"
-    if db.stmt != nil:
-      properFreeResult(SQL_HANDLE_STMT, db.stmt)
-    properFreeResult(SQL_HANDLE_DBC, db.hDb)
-    properFreeResult(SQL_HANDLE_ENV, db.env)
-    raise e
-
-proc sqlCheck(db: var DbConn, resVal: TSqlSmallInt) {.raises: [DbError]} =
-  ## Wrapper that raises [EDb] if `resVal` is neither SQL_SUCCESS or SQL_NO_DATA
-  if resVal notIn [SQL_SUCCESS, SQL_NO_DATA]: dbError(db)
-
-proc sqlGetDBMS(db: var DbConn): string {.
-        tags: [ReadDbEffect, WriteDbEffect], raises: [] .} =
-  ## Returns the ODBC SQL_DBMS_NAME string
-  const
-    SQL_DBMS_NAME = 17.SqlUSmallInt
-  var
-    sz: TSqlSmallInt = 0
-  buf[0] = '\0'
-  try:
-    db.sqlCheck(SQLGetInfo(db.hDb, SQL_DBMS_NAME, cast[SqlPointer](buf.addr),
-                        4095.TSqlSmallInt, sz.addr))
-  except: discard
-  return $(addr buf)
-
-proc dbQuote*(s: string): string {.noSideEffect.} =
-  ## DB quotes the string.
-  result = "'"
-  for c in items(s):
-    if c == '\'': add(result, "''")
-    else: add(result, c)
-  add(result, '\'')
-
-proc dbFormat(formatstr: SqlQuery, args: varargs[string]): string {.
-                  noSideEffect.} =
-  ## Replace any `?` placeholders with `args`,
-  ## and quotes the arguments
-  result = ""
-  var a = 0
-  for c in items(string(formatstr)):
-    if c == '?':
-      add(result, dbQuote(args[a]))
-      inc(a)
-    else:
-      add(result, c)
-
-proc prepareFetch(db: var DbConn, query: SqlQuery,
-                args: varargs[string, `$`]): TSqlSmallInt {.
-                tags: [ReadDbEffect, WriteDbEffect], raises: [DbError].} =
-  # Prepare a statement, execute it and fetch the data to the driver
-  # ready for retrieval of the data
-  # Used internally by iterators and retrieval procs
-  # requires calling
-  #      properFreeResult(SQL_HANDLE_STMT, db.stmt)
-  # when finished
-  db.sqlCheck(SQLAllocHandle(SQL_HANDLE_STMT, db.hDb, db.stmt))
-  var q = dbFormat(query, args)
-  db.sqlCheck(SQLPrepare(db.stmt, q.PSQLCHAR, q.len.TSqlSmallInt))
-  db.sqlCheck(SQLExecute(db.stmt))
-  result = SQLFetch(db.stmt)
-  db.sqlCheck(result)
-
-proc prepareFetchDirect(db: var DbConn, query: SqlQuery,
-                args: varargs[string, `$`]) {.
-                tags: [ReadDbEffect, WriteDbEffect], raises: [DbError].} =
-  # Prepare a statement, execute it and fetch the data to the driver
-  # ready for retrieval of the data
-  # Used internally by iterators and retrieval procs
-  # requires calling
-  #      properFreeResult(SQL_HANDLE_STMT, db.stmt)
-  # when finished
-  db.sqlCheck(SQLAllocHandle(SQL_HANDLE_STMT, db.hDb, db.stmt))
-  var q = dbFormat(query, args)
-  db.sqlCheck(SQLExecDirect(db.stmt, q.PSQLCHAR, q.len.TSqlSmallInt))
-  db.sqlCheck(SQLFetch(db.stmt))
-
-proc tryExec*(db: var DbConn, query: SqlQuery, args: varargs[string, `$`]): bool {.
-  tags: [ReadDbEffect, WriteDbEffect], raises: [].} =
-  ## Tries to execute the query and returns true if successful, false otherwise.
-  var
-    res:TSqlSmallInt = -1
-  try:
-    db.prepareFetchDirect(query, args)
-    var
-      rCnt:TSqlLen = -1
-    res = SQLRowCount(db.stmt, rCnt)
-    properFreeResult(SQL_HANDLE_STMT, db.stmt)
-    if res != SQL_SUCCESS: dbError(db)
-  except: discard
-  return res == SQL_SUCCESS
-
-proc rawExec(db: var DbConn, query: SqlQuery, args: varargs[string, `$`]) {.
-            tags: [ReadDbEffect, WriteDbEffect], raises: [DbError].} =
-  db.prepareFetchDirect(query, args)
-
-proc exec*(db: var DbConn, query: SqlQuery, args: varargs[string, `$`]) {.
-            tags: [ReadDbEffect, WriteDbEffect], raises: [DbError].} =
-  ## Executes the query and raises EDB if not successful.
-  db.prepareFetchDirect(query, args)
-  properFreeResult(SQL_HANDLE_STMT, db.stmt)
-
-proc newRow(L: int): Row {.noSideEFfect.} =
-  newSeq(result, L)
-  for i in 0..L-1: result[i] = ""
-
-iterator fastRows*(db: var DbConn, query: SqlQuery,
-                   args: varargs[string, `$`]): Row {.
-                tags: [ReadDbEffect, WriteDbEffect], raises: [DbError].} =
-  ## Executes the query and iterates over the result dataset.
-  ##
-  ## This is very fast, but potentially dangerous.  Use this iterator only
-  ## if you require **ALL** the rows.
-  ##
-  ## Breaking the fastRows() iterator during a loop may cause a driver error
-  ## for subsequent queries
-  ##
-  ## Rows are retrieved from the server at each iteration.
-  var
-    rowRes: Row
-    sz: TSqlLen = 0
-    cCnt: TSqlSmallInt = 0
-    res: TSqlSmallInt = 0
-  res = db.prepareFetch(query, args)
-  if res == SQL_NO_DATA:
-    discard
-  elif res == SQL_SUCCESS:
-    res = SQLNumResultCols(db.stmt, cCnt)
-    rowRes = newRow(cCnt)
-    rowRes.setLen(max(cCnt,0))
-    while res == SQL_SUCCESS:
-      for colId in 1..cCnt:
-        buf[0] = '\0'
-        db.sqlCheck(SQLGetData(db.stmt, colId.SqlUSmallInt, SQL_C_CHAR,
-                                 cast[cstring](buf.addr), 4095, sz.addr))
-        rowRes[colId-1] = $(addr buf)
-      yield rowRes
-      res = SQLFetch(db.stmt)
-  properFreeResult(SQL_HANDLE_STMT, db.stmt)
-  db.sqlCheck(res)
-
-iterator instantRows*(db: var DbConn, query: SqlQuery,
-                      args: varargs[string, `$`]): InstantRow
-                {.tags: [ReadDbEffect, WriteDbEffect].} =
-  ## Same as fastRows but returns a handle that can be used to get column text
-  ## on demand using []. Returned handle is valid only within the iterator body.
-  var
-    rowRes: Row = @[]
-    sz: TSqlLen = 0
-    cCnt: TSqlSmallInt = 0
-    res: TSqlSmallInt = 0
-  res = db.prepareFetch(query, args)
-  if res == SQL_NO_DATA:
-    discard
-  elif res == SQL_SUCCESS:
-    res = SQLNumResultCols(db.stmt, cCnt)
-    rowRes = newRow(cCnt)
-    rowRes.setLen(max(cCnt,0))
-    while res == SQL_SUCCESS:
-      for colId in 1..cCnt:
-        buf[0] = '\0'
-        db.sqlCheck(SQLGetData(db.stmt, colId.SqlUSmallInt, SQL_C_CHAR,
-                                 cast[cstring](buf.addr), 4095, sz.addr))
-        rowRes[colId-1] = $(addr buf)
-      yield (row: rowRes, len: cCnt.int)
-      res = SQLFetch(db.stmt)
-  properFreeResult(SQL_HANDLE_STMT, db.stmt)
-  db.sqlCheck(res)
-
-proc `[]`*(row: InstantRow, col: int): string {.inline.} =
-  ## Returns text for given column of the row
-  $row.row[col]
-
-proc unsafeColumnAt*(row: InstantRow, index: int): cstring {.inline.} =
-  ## Return cstring of given column of the row
-  row.row[index]
-
-proc len*(row: InstantRow): int {.inline.} =
-  ## Returns number of columns in the row
-  row.len
-
-proc getRow*(db: var DbConn, query: SqlQuery,
-             args: varargs[string, `$`]): Row {.
-          tags: [ReadDbEffect, WriteDbEffect], raises: [DbError].} =
-  ## Retrieves a single row. If the query doesn't return any rows, this proc
-  ## will return a Row with empty strings for each column.
-  var
-    rowRes: Row
-    sz: TSqlLen = 0
-    cCnt: TSqlSmallInt = 0
-    res: TSqlSmallInt = 0
-  res = db.prepareFetch(query, args)
-  if res == SQL_NO_DATA:
-    result = @[]
-  elif res == SQL_SUCCESS:
-    res = SQLNumResultCols(db.stmt, cCnt)
-    rowRes = newRow(cCnt)
-    rowRes.setLen(max(cCnt,0))
-    for colId in 1..cCnt:
-      buf[0] = '\0'
-      db.sqlCheck(SQLGetData(db.stmt, colId.SqlUSmallInt, SQL_C_CHAR,
-                               cast[cstring](buf.addr), 4095, sz.addr))
-      rowRes[colId-1] = $(addr buf)
-    res = SQLFetch(db.stmt)
-    result = rowRes
-  properFreeResult(SQL_HANDLE_STMT, db.stmt)
-  db.sqlCheck(res)
-
-proc getAllRows*(db: var DbConn, query: SqlQuery,
-                 args: varargs[string, `$`]): seq[Row] {.
-           tags: [ReadDbEffect, WriteDbEffect], raises: [DbError] .} =
-  ## Executes the query and returns the whole result dataset.
-  var
-    rows: seq[Row] = @[]
-    rowRes: Row
-    sz: TSqlLen = 0
-    cCnt: TSqlSmallInt = 0
-    res: TSqlSmallInt = 0
-  res = db.prepareFetch(query, args)
-  if res == SQL_NO_DATA:
-    result = @[]
-  elif res == SQL_SUCCESS:
-    res = SQLNumResultCols(db.stmt, cCnt)
-    rowRes = newRow(cCnt)
-    rowRes.setLen(max(cCnt,0))
-    while res == SQL_SUCCESS:
-      for colId in 1..cCnt:
-        buf[0] = '\0'
-        db.sqlCheck(SQLGetData(db.stmt, colId.SqlUSmallInt, SQL_C_CHAR,
-                                 cast[cstring](buf.addr), 4095, sz.addr))
-        rowRes[colId-1] = $(addr buf)
-      rows.add(rowRes)
-      res = SQLFetch(db.stmt)
-    result = rows
-  properFreeResult(SQL_HANDLE_STMT, db.stmt)
-  db.sqlCheck(res)
-
-iterator rows*(db: var DbConn, query: SqlQuery,
-               args: varargs[string, `$`]): Row {.
-         tags: [ReadDbEffect, WriteDbEffect], raises: [DbError].} =
-  ## Same as `fastRows`, but slower and safe.
-  ##
-  ## This retrieves ALL rows into memory before
-  ## iterating through the rows.
-  ## Large dataset queries will impact on memory usage.
-  for r in items(getAllRows(db, query, args)): yield r
-
-proc getValue*(db: var DbConn, query: SqlQuery,
-               args: varargs[string, `$`]): string {.
-           tags: [ReadDbEffect, WriteDbEffect], raises: [].} =
-  ## Executes the query and returns the first column of the first row of the
-  ## result dataset. Returns "" if the dataset contains no rows or the database
-  ## value is NULL.
-  result = ""
-  try:
-    result = getRow(db, query, args)[0]
-  except: discard
-
-proc tryInsertId*(db: var DbConn, query: SqlQuery,
-                  args: varargs[string, `$`]): int64 {.
-            tags: [ReadDbEffect, WriteDbEffect], raises: [].} =
-  ## Executes the query (typically "INSERT") and returns the
-  ## generated ID for the row or -1 in case of an error.
-  if not tryExec(db, query, args):
-    result = -1'i64
-  else:
-    result = -1'i64
-    try:
-      case sqlGetDBMS(db).toLower():
-      of "postgresql":
-        result = getValue(db, sql"SELECT LASTVAL();", []).parseInt
-      of "mysql":
-        result = getValue(db, sql"SELECT LAST_INSERT_ID();", []).parseInt
-      of "sqlite":
-        result = getValue(db, sql"SELECT LAST_INSERT_ROWID();", []).parseInt
-      of "microsoft sql server":
-        result = getValue(db, sql"SELECT SCOPE_IDENTITY();", []).parseInt
-      of "oracle":
-        result = getValue(db, sql"SELECT id.currval FROM DUAL;", []).parseInt
-      else: result = -1'i64
-    except: discard
-
-proc insertId*(db: var DbConn, query: SqlQuery,
-               args: varargs[string, `$`]): int64 {.
-         tags: [ReadDbEffect, WriteDbEffect], raises: [DbError].} =
-  ## Executes the query (typically "INSERT") and returns the
-  ## generated ID for the row.
-  result = tryInsertID(db, query, args)
-  if result < 0: dbError(db)
-
-proc tryInsert*(db: var DbConn, query: SqlQuery,pkName: string,
-                args: varargs[string, `$`]): int64
-               {.tags: [ReadDbEffect, WriteDbEffect], raises: [], since: (1, 3).} =
-  ## same as tryInsertID
-  tryInsertID(db, query, args)
-
-proc insert*(db: var DbConn, query: SqlQuery, pkName: string,
-             args: varargs[string, `$`]): int64 
-            {.tags: [ReadDbEffect, WriteDbEffect], since: (1, 3).} =
-  ## same as insertId
-  result = tryInsert(db, query,pkName, args)
-  if result < 0: dbError(db)
-
-proc execAffectedRows*(db: var DbConn, query: SqlQuery,
-                       args: varargs[string, `$`]): int64 {.
-             tags: [ReadDbEffect, WriteDbEffect], raises: [DbError].} =
-  ## Runs the query (typically "UPDATE") and returns the
-  ## number of affected rows
-  result = -1
-  db.sqlCheck(SQLAllocHandle(SQL_HANDLE_STMT, db.hDb, db.stmt.SqlHandle))
-  var q = dbFormat(query, args)
-  db.sqlCheck(SQLPrepare(db.stmt, q.PSQLCHAR, q.len.TSqlSmallInt))
-  rawExec(db, query, args)
-  var rCnt:TSqlLen = -1
-  db.sqlCheck(SQLRowCount(db.hDb, rCnt))
-  properFreeResult(SQL_HANDLE_STMT, db.stmt)
-  result = rCnt.int64
-
-proc close*(db: var DbConn) {.
-      tags: [WriteDbEffect], raises: [].} =
-  ## Closes the database connection.
-  if db.hDb != nil:
-    try:
-      var res = SQLDisconnect(db.hDb)
-      if db.stmt != nil:
-        res = SQLFreeHandle(SQL_HANDLE_STMT, db.stmt)
-      res = SQLFreeHandle(SQL_HANDLE_DBC, db.hDb)
-      res = SQLFreeHandle(SQL_HANDLE_ENV, db.env)
-      db = (hDb: nil, env: nil, stmt: nil)
-    except:
-      discard
-
-proc open*(connection, user, password, database: string): DbConn {.
-  tags: [ReadDbEffect, WriteDbEffect], raises: [DbError].} =
-  ## Opens a database connection.
-  ##
-  ## Raises `EDb` if the connection could not be established.
-  ##
-  ## Currently the database parameter is ignored,
-  ## but included to match `open()` in the other db_xxxxx library modules.
-  var
-    val = SQL_OV_ODBC3
-    resLen = 0
-  result = (hDb: nil, env: nil, stmt: nil)
-  # allocate environment handle
-  var res = SQLAllocHandle(SQL_HANDLE_ENV, result.env, result.env)
-  if res != SQL_SUCCESS: dbError("Error: unable to initialise ODBC environment.")
-  res = SQLSetEnvAttr(result.env,
-                      SQL_ATTR_ODBC_VERSION.TSqlInteger,
-                      cast[SqlPointer](val), resLen.TSqlInteger)
-  if res != SQL_SUCCESS: dbError("Error: unable to set ODBC driver version.")
-  # allocate hDb handle
-  res = SQLAllocHandle(SQL_HANDLE_DBC, result.env, result.hDb)
-  if res != SQL_SUCCESS: dbError("Error: unable to allocate connection handle.")
-
-  # Connect: connection = dsn str,
-  res = SQLConnect(result.hDb,
-                  connection.PSQLCHAR , connection.len.TSqlSmallInt,
-                  user.PSQLCHAR, user.len.TSqlSmallInt,
-                  password.PSQLCHAR, password.len.TSqlSmallInt)
-  if res != SQL_SUCCESS:
-    result.dbError()
-
-proc setEncoding*(connection: DbConn, encoding: string): bool {.
-  tags: [ReadDbEffect, WriteDbEffect], raises: [DbError].} =
-  ## Currently not implemented for ODBC.
-  ##
-  ## Sets the encoding of a database connection, returns true for
-  ## success, false for failure.
-  ##result = set_character_set(connection, encoding) == 0
-  dbError("setEncoding() is currently not implemented by the db_odbc module")
diff --git a/lib/impure/db_postgres.nim b/lib/impure/db_postgres.nim
deleted file mode 100644
index 034a94852..000000000
--- a/lib/impure/db_postgres.nim
+++ /dev/null
@@ -1,590 +0,0 @@
-#
-#
-#            Nim's Runtime Library
-#        (c) Copyright 2015 Andreas Rumpf
-#
-#    See the file "copying.txt", included in this
-#    distribution, for details about the copyright.
-#
-
-## A higher level `PostgreSQL`:idx: database wrapper. This interface
-## is implemented for other databases also.
-##
-## See also: `db_odbc <db_odbc.html>`_, `db_sqlite <db_sqlite.html>`_,
-## `db_mysql <db_mysql.html>`_.
-##
-## Parameter substitution
-## ======================
-##
-## All `db_*` modules support the same form of parameter substitution.
-## That is, using the `?` (question mark) to signify the place where a
-## value should be placed. For example:
-##
-## .. code-block:: Nim
-##     sql"INSERT INTO myTable (colA, colB, colC) VALUES (?, ?, ?)"
-##
-## **Note**: There are two approaches to parameter substitution support by
-## this module.
-##
-## 1. `SqlQuery` using `?, ?, ?, ...` (same as all the `db_*` modules)
-##
-## 2. `SqlPrepared` using `$1, $2, $3, ...`
-##
-## .. code-block:: Nim
-##   prepare(db, "myExampleInsert",
-##           sql"""INSERT INTO myTable
-##                 (colA, colB, colC)
-##                 VALUES ($1, $2, $3)""",
-##           3)
-##
-##
-## Unix Socket
-## ===========
-##
-## Using Unix sockets instead of TCP connection can
-## `improve performance up to 30% ~ 175% for some operations <https://momjian.us/main/blogs/pgblog/2012.html#June_6_2012>`_.
-##
-## To use Unix sockets with `db_postgres`, change the server address to the socket file path:
-##
-## .. code-block:: Nim
-##   import std/db_postgres ## Change "localhost" or "127.0.0.1" to the socket file path
-##   let db = db_postgres.open("/run/postgresql", "user", "password", "database")
-##   echo db.getAllRows(sql"SELECT version();")
-##   db.close()
-##
-## The socket file path is operating system specific and distribution specific,
-## additional configuration may or may not be needed on your `postgresql.conf`.
-## The Postgres server must be on the same computer and only works for Unix-like operating systems.
-##
-##
-## Examples
-## ========
-##
-## Opening a connection to a database
-## ----------------------------------
-##
-## .. code-block:: Nim
-##     import std/db_postgres
-##     let db = open("localhost", "user", "password", "dbname")
-##     db.close()
-##
-## Creating a table
-## ----------------
-##
-## .. code-block:: Nim
-##      db.exec(sql"DROP TABLE IF EXISTS myTable")
-##      db.exec(sql("""CREATE TABLE myTable (
-##                       id integer,
-##                       name varchar(50) not null)"""))
-##
-## Inserting data
-## --------------
-##
-## .. code-block:: Nim
-##     db.exec(sql"INSERT INTO myTable (id, name) VALUES (0, ?)",
-##             "Dominik")
-import strutils, postgres
-
-import db_common
-export db_common
-
-import std/private/since
-
-type
-  DbConn* = PPGconn    ## encapsulates a database connection
-  Row* = seq[string]   ## a row of a dataset. NULL database values will be
-                       ## converted to nil.
-  InstantRow* = object ## a handle that can be
-    res: PPGresult     ## used to get a row's
-    line: int          ## column text on demand
-  SqlPrepared* = distinct string ## a identifier for the prepared queries
-
-proc dbError*(db: DbConn) {.noreturn.} =
-  ## raises a DbError exception.
-  var e: ref DbError
-  new(e)
-  e.msg = $pqErrorMessage(db)
-  raise e
-
-proc dbQuote*(s: string): string =
-  ## DB quotes the string.
-  result = "'"
-  for c in items(s):
-    if c == '\'': add(result, "''")
-    else: add(result, c)
-  add(result, '\'')
-
-proc dbFormat(formatstr: SqlQuery, args: varargs[string]): string =
-  result = ""
-  var a = 0
-  if args.len > 0 and not string(formatstr).contains("?"):
-    dbError("""parameter substitution expects "?" """)
-  if args.len == 0:
-    return string(formatstr)
-  else:
-    for c in items(string(formatstr)):
-      if c == '?':
-        add(result, dbQuote(args[a]))
-        inc(a)
-      else:
-        add(result, c)
-
-proc tryExec*(db: DbConn, query: SqlQuery,
-              args: varargs[string, `$`]): bool {.tags: [ReadDbEffect, WriteDbEffect].} =
-  ## tries to execute the query and returns true if successful, false otherwise.
-  var res = pqexecParams(db, dbFormat(query, args), 0, nil, nil,
-                        nil, nil, 0)
-  result = pqresultStatus(res) == PGRES_COMMAND_OK
-  pqclear(res)
-
-proc tryExec*(db: DbConn, stmtName: SqlPrepared,
-              args: varargs[string, `$`]): bool {.tags: [
-              ReadDbEffect, WriteDbEffect].} =
-  ## tries to execute the query and returns true if successful, false otherwise.
-  var arr = allocCStringArray(args)
-  var res = pqexecPrepared(db, stmtName.string, int32(args.len), arr,
-                           nil, nil, 0)
-  deallocCStringArray(arr)
-  result = pqresultStatus(res) == PGRES_COMMAND_OK
-  pqclear(res)
-
-proc exec*(db: DbConn, query: SqlQuery, args: varargs[string, `$`]) {.
-  tags: [ReadDbEffect, WriteDbEffect].} =
-  ## executes the query and raises EDB if not successful.
-  var res = pqexecParams(db, dbFormat(query, args), 0, nil, nil,
-                        nil, nil, 0)
-  if pqresultStatus(res) != PGRES_COMMAND_OK: dbError(db)
-  pqclear(res)
-
-proc exec*(db: DbConn, stmtName: SqlPrepared,
-          args: varargs[string]) {.tags: [ReadDbEffect, WriteDbEffect].} =
-  var arr = allocCStringArray(args)
-  var res = pqexecPrepared(db, stmtName.string, int32(args.len), arr,
-                           nil, nil, 0)
-  deallocCStringArray(arr)
-  if pqResultStatus(res) != PGRES_COMMAND_OK: dbError(db)
-  pqclear(res)
-
-proc newRow(L: int): Row =
-  newSeq(result, L)
-  for i in 0..L-1: result[i] = ""
-
-proc setupQuery(db: DbConn, query: SqlQuery,
-                args: varargs[string]): PPGresult =
-  result = pqexec(db, dbFormat(query, args))
-  if pqResultStatus(result) != PGRES_TUPLES_OK: dbError(db)
-
-proc setupQuery(db: DbConn, stmtName: SqlPrepared,
-                 args: varargs[string]): PPGresult =
-  var arr = allocCStringArray(args)
-  result = pqexecPrepared(db, stmtName.string, int32(args.len), arr,
-                          nil, nil, 0)
-  deallocCStringArray(arr)
-  if pqResultStatus(result) != PGRES_TUPLES_OK: dbError(db)
-
-proc prepare*(db: DbConn; stmtName: string, query: SqlQuery;
-              nParams: int): SqlPrepared =
-  ## Creates a new `SqlPrepared` statement. Parameter substitution is done
-  ## via `$1`, `$2`, `$3`, etc.
-  if nParams > 0 and not string(query).contains("$1"):
-    dbError("parameter substitution expects \"$1\"")
-  var res = pqprepare(db, stmtName, query.string, int32(nParams), nil)
-  if pqResultStatus(res) != PGRES_COMMAND_OK: dbError(db)
-  return SqlPrepared(stmtName)
-
-proc setRow(res: PPGresult, r: var Row, line, cols: int32) =
-  for col in 0'i32..cols-1:
-    setLen(r[col], 0)
-    let x = pqgetvalue(res, line, col)
-    if x.isNil:
-      r[col] = ""
-    else:
-      add(r[col], x)
-
-iterator fastRows*(db: DbConn, query: SqlQuery,
-                   args: varargs[string, `$`]): Row {.tags: [ReadDbEffect].} =
-  ## executes the query and iterates over the result dataset. This is very
-  ## fast, but potentially dangerous: If the for-loop-body executes another
-  ## query, the results can be undefined. For Postgres it is safe though.
-  var res = setupQuery(db, query, args)
-  var L = pqnfields(res)
-  var result = newRow(L)
-  for i in 0'i32..pqntuples(res)-1:
-    setRow(res, result, i, L)
-    yield result
-  pqclear(res)
-
-iterator fastRows*(db: DbConn, stmtName: SqlPrepared,
-                   args: varargs[string, `$`]): Row {.tags: [ReadDbEffect].} =
-  ## executes the prepared query and iterates over the result dataset.
-  var res = setupQuery(db, stmtName, args)
-  var L = pqNfields(res)
-  var result = newRow(L)
-  for i in 0'i32..pqNtuples(res)-1:
-    setRow(res, result, i, L)
-    yield result
-  pqClear(res)
-
-iterator instantRows*(db: DbConn, query: SqlQuery,
-                      args: varargs[string, `$`]): InstantRow
-                      {.tags: [ReadDbEffect].} =
-  ## same as fastRows but returns a handle that can be used to get column text
-  ## on demand using []. Returned handle is valid only within iterator body.
-  var res = setupQuery(db, query, args)
-  for i in 0'i32..pqNtuples(res)-1:
-    yield InstantRow(res: res, line: i)
-  pqClear(res)
-
-iterator instantRows*(db: DbConn, stmtName: SqlPrepared,
-                      args: varargs[string, `$`]): InstantRow
-                      {.tags: [ReadDbEffect].} =
-  ## same as fastRows but returns a handle that can be used to get column text
-  ## on demand using []. Returned handle is valid only within iterator body.
-  var res = setupQuery(db, stmtName, args)
-  for i in 0'i32..pqNtuples(res)-1:
-    yield InstantRow(res: res, line: i)
-  pqClear(res)
-
-proc getColumnType(res: PPGresult, col: int) : DbType =
-  ## returns DbType for given column in the row
-  ## defined in pg_type.h file in the postgres source code
-  ## Wire representation for types: http://www.npgsql.org/dev/types.html
-  var oid = pqftype(res, int32(col))
-  ## The integer returned is the internal OID number of the type
-  case oid
-  of 16: return DbType(kind: DbTypeKind.dbBool, name: "bool")
-  of 17: return DbType(kind: DbTypeKind.dbBlob, name: "bytea")
-
-  of 21:   return DbType(kind: DbTypeKind.dbInt, name: "int2", size: 2)
-  of 23:   return DbType(kind: DbTypeKind.dbInt, name: "int4", size: 4)
-  of 20:   return DbType(kind: DbTypeKind.dbInt, name: "int8", size: 8)
-  of 1560: return DbType(kind: DbTypeKind.dbBit, name: "bit")
-  of 1562: return DbType(kind: DbTypeKind.dbInt, name: "varbit")
-
-  of 18:   return DbType(kind: DbTypeKind.dbFixedChar, name: "char")
-  of 19:   return DbType(kind: DbTypeKind.dbFixedChar, name: "name")
-  of 1042: return DbType(kind: DbTypeKind.dbFixedChar, name: "bpchar")
-
-  of 25:   return DbType(kind: DbTypeKind.dbVarchar, name: "text")
-  of 1043: return DbType(kind: DbTypeKind.dbVarChar, name: "varchar")
-  of 2275: return DbType(kind: DbTypeKind.dbVarchar, name: "cstring")
-
-  of 700: return DbType(kind: DbTypeKind.dbFloat, name: "float4")
-  of 701: return DbType(kind: DbTypeKind.dbFloat, name: "float8")
-
-  of 790:  return DbType(kind: DbTypeKind.dbDecimal, name: "money")
-  of 1700: return DbType(kind: DbTypeKind.dbDecimal, name: "numeric")
-
-  of 704:  return DbType(kind: DbTypeKind.dbTimeInterval, name: "tinterval")
-  of 702:  return DbType(kind: DbTypeKind.dbTimestamp, name: "abstime")
-  of 703:  return DbType(kind: DbTypeKind.dbTimeInterval, name: "reltime")
-  of 1082: return DbType(kind: DbTypeKind.dbDate, name: "date")
-  of 1083: return DbType(kind: DbTypeKind.dbTime, name: "time")
-  of 1114: return DbType(kind: DbTypeKind.dbTimestamp, name: "timestamp")
-  of 1184: return DbType(kind: DbTypeKind.dbTimestamp, name: "timestamptz")
-  of 1186: return DbType(kind: DbTypeKind.dbTimeInterval, name: "interval")
-  of 1266: return DbType(kind: DbTypeKind.dbTime, name: "timetz")
-
-  of 114:  return DbType(kind: DbTypeKind.dbJson, name: "json")
-  of 142:  return DbType(kind: DbTypeKind.dbXml, name: "xml")
-  of 3802: return DbType(kind: DbTypeKind.dbJson, name: "jsonb")
-
-  of 600: return DbType(kind: DbTypeKind.dbPoint, name: "point")
-  of 601: return DbType(kind: DbTypeKind.dbLseg, name: "lseg")
-  of 602: return DbType(kind: DbTypeKind.dbPath, name: "path")
-  of 603: return DbType(kind: DbTypeKind.dbBox, name: "box")
-  of 604: return DbType(kind: DbTypeKind.dbPolygon, name: "polygon")
-  of 628: return DbType(kind: DbTypeKind.dbLine, name: "line")
-  of 718: return DbType(kind: DbTypeKind.dbCircle, name: "circle")
-
-  of 650: return DbType(kind: DbTypeKind.dbInet, name: "cidr")
-  of 829: return DbType(kind: DbTypeKind.dbMacAddress, name: "macaddr")
-  of 869: return DbType(kind: DbTypeKind.dbInet, name: "inet")
-
-  of 2950: return DbType(kind: DbTypeKind.dbVarchar, name: "uuid")
-  of 3614: return DbType(kind: DbTypeKind.dbVarchar, name: "tsvector")
-  of 3615: return DbType(kind: DbTypeKind.dbVarchar, name: "tsquery")
-  of 2970: return DbType(kind: DbTypeKind.dbVarchar, name: "txid_snapshot")
-
-  of 27:   return DbType(kind: DbTypeKind.dbComposite, name: "tid")
-  of 1790: return DbType(kind: DbTypeKind.dbComposite, name: "refcursor")
-  of 2249: return DbType(kind: DbTypeKind.dbComposite, name: "record")
-  of 3904: return DbType(kind: DbTypeKind.dbComposite, name: "int4range")
-  of 3906: return DbType(kind: DbTypeKind.dbComposite, name: "numrange")
-  of 3908: return DbType(kind: DbTypeKind.dbComposite, name: "tsrange")
-  of 3910: return DbType(kind: DbTypeKind.dbComposite, name: "tstzrange")
-  of 3912: return DbType(kind: DbTypeKind.dbComposite, name: "daterange")
-  of 3926: return DbType(kind: DbTypeKind.dbComposite, name: "int8range")
-
-  of 22:   return DbType(kind: DbTypeKind.dbArray, name: "int2vector")
-  of 30:   return DbType(kind: DbTypeKind.dbArray, name: "oidvector")
-  of 143:  return DbType(kind: DbTypeKind.dbArray, name: "xml[]")
-  of 199:  return DbType(kind: DbTypeKind.dbArray, name: "json[]")
-  of 629:  return DbType(kind: DbTypeKind.dbArray, name: "line[]")
-  of 651:  return DbType(kind: DbTypeKind.dbArray, name: "cidr[]")
-  of 719:  return DbType(kind: DbTypeKind.dbArray, name: "circle[]")
-  of 791:  return DbType(kind: DbTypeKind.dbArray, name: "money[]")
-  of 1000: return DbType(kind: DbTypeKind.dbArray, name: "bool[]")
-  of 1001: return DbType(kind: DbTypeKind.dbArray, name: "bytea[]")
-  of 1002: return DbType(kind: DbTypeKind.dbArray, name: "char[]")
-  of 1003: return DbType(kind: DbTypeKind.dbArray, name: "name[]")
-  of 1005: return DbType(kind: DbTypeKind.dbArray, name: "int2[]")
-  of 1006: return DbType(kind: DbTypeKind.dbArray, name: "int2vector[]")
-  of 1007: return DbType(kind: DbTypeKind.dbArray, name: "int4[]")
-  of 1008: return DbType(kind: DbTypeKind.dbArray, name: "regproc[]")
-  of 1009: return DbType(kind: DbTypeKind.dbArray, name: "text[]")
-  of 1028: return DbType(kind: DbTypeKind.dbArray, name: "oid[]")
-  of 1010: return DbType(kind: DbTypeKind.dbArray, name: "tid[]")
-  of 1011: return DbType(kind: DbTypeKind.dbArray, name: "xid[]")
-  of 1012: return DbType(kind: DbTypeKind.dbArray, name: "cid[]")
-  of 1013: return DbType(kind: DbTypeKind.dbArray, name: "oidvector[]")
-  of 1014: return DbType(kind: DbTypeKind.dbArray, name: "bpchar[]")
-  of 1015: return DbType(kind: DbTypeKind.dbArray, name: "varchar[]")
-  of 1016: return DbType(kind: DbTypeKind.dbArray, name: "int8[]")
-  of 1017: return DbType(kind: DbTypeKind.dbArray, name: "point[]")
-  of 1018: return DbType(kind: DbTypeKind.dbArray, name: "lseg[]")
-  of 1019: return DbType(kind: DbTypeKind.dbArray, name: "path[]")
-  of 1020: return DbType(kind: DbTypeKind.dbArray, name: "box[]")
-  of 1021: return DbType(kind: DbTypeKind.dbArray, name: "float4[]")
-  of 1022: return DbType(kind: DbTypeKind.dbArray, name: "float8[]")
-  of 1023: return DbType(kind: DbTypeKind.dbArray, name: "abstime[]")
-  of 1024: return DbType(kind: DbTypeKind.dbArray, name: "reltime[]")
-  of 1025: return DbType(kind: DbTypeKind.dbArray, name: "tinterval[]")
-  of 1027: return DbType(kind: DbTypeKind.dbArray, name: "polygon[]")
-  of 1040: return DbType(kind: DbTypeKind.dbArray, name: "macaddr[]")
-  of 1041: return DbType(kind: DbTypeKind.dbArray, name: "inet[]")
-  of 1263: return DbType(kind: DbTypeKind.dbArray, name: "cstring[]")
-  of 1115: return DbType(kind: DbTypeKind.dbArray, name: "timestamp[]")
-  of 1182: return DbType(kind: DbTypeKind.dbArray, name: "date[]")
-  of 1183: return DbType(kind: DbTypeKind.dbArray, name: "time[]")
-  of 1185: return DbType(kind: DbTypeKind.dbArray, name: "timestamptz[]")
-  of 1187: return DbType(kind: DbTypeKind.dbArray, name: "interval[]")
-  of 1231: return DbType(kind: DbTypeKind.dbArray, name: "numeric[]")
-  of 1270: return DbType(kind: DbTypeKind.dbArray, name: "timetz[]")
-  of 1561: return DbType(kind: DbTypeKind.dbArray, name: "bit[]")
-  of 1563: return DbType(kind: DbTypeKind.dbArray, name: "varbit[]")
-  of 2201: return DbType(kind: DbTypeKind.dbArray, name: "refcursor[]")
-  of 2951: return DbType(kind: DbTypeKind.dbArray, name: "uuid[]")
-  of 3643: return DbType(kind: DbTypeKind.dbArray, name: "tsvector[]")
-  of 3645: return DbType(kind: DbTypeKind.dbArray, name: "tsquery[]")
-  of 3807: return DbType(kind: DbTypeKind.dbArray, name: "jsonb[]")
-  of 2949: return DbType(kind: DbTypeKind.dbArray, name: "txid_snapshot[]")
-  of 3905: return DbType(kind: DbTypeKind.dbArray, name: "int4range[]")
-  of 3907: return DbType(kind: DbTypeKind.dbArray, name: "numrange[]")
-  of 3909: return DbType(kind: DbTypeKind.dbArray, name: "tsrange[]")
-  of 3911: return DbType(kind: DbTypeKind.dbArray, name: "tstzrange[]")
-  of 3913: return DbType(kind: DbTypeKind.dbArray, name: "daterange[]")
-  of 3927: return DbType(kind: DbTypeKind.dbArray, name: "int8range[]")
-  of 2287: return DbType(kind: DbTypeKind.dbArray, name: "record[]")
-
-  of 705:  return DbType(kind: DbTypeKind.dbUnknown, name: "unknown")
-  else: return DbType(kind: DbTypeKind.dbUnknown, name: $oid) ## Query the system table pg_type to determine exactly which type is referenced.
-
-proc setColumnInfo(columns: var DbColumns; res: PPGresult; L: int32) =
-  setLen(columns, L)
-  for i in 0'i32..<L:
-    columns[i].name = $pqfname(res, i)
-    columns[i].typ = getColumnType(res, i)
-    columns[i].tableName = $(pqftable(res, i)) ## Returns the OID of the table from which the given column was fetched.
-                                               ## Query the system table pg_class to determine exactly which table is referenced.
-    #columns[i].primaryKey = libpq does not have a function for that
-    #columns[i].foreignKey = libpq does not have a function for that
-
-iterator instantRows*(db: DbConn; columns: var DbColumns; query: SqlQuery;
-                      args: varargs[string, `$`]): InstantRow
-                      {.tags: [ReadDbEffect].} =
-  var res = setupQuery(db, query, args)
-  setColumnInfo(columns, res, pqnfields(res))
-  for i in 0'i32..<pqntuples(res):
-    yield InstantRow(res: res, line: i)
-  pqClear(res)
-
-proc `[]`*(row: InstantRow; col: int): string {.inline.} =
-  ## returns text for given column of the row
-  $pqgetvalue(row.res, int32(row.line), int32(col))
-
-proc unsafeColumnAt*(row: InstantRow, index: int): cstring {.inline.} =
-  ## Return cstring of given column of the row
-  pqgetvalue(row.res, int32(row.line), int32(index))
-
-proc len*(row: InstantRow): int {.inline.} =
-  ## returns number of columns in the row
-  int(pqNfields(row.res))
-
-proc getRow*(db: DbConn, query: SqlQuery,
-             args: varargs[string, `$`]): Row {.tags: [ReadDbEffect].} =
-  ## retrieves a single row. If the query doesn't return any rows, this proc
-  ## will return a Row with empty strings for each column.
-  var res = setupQuery(db, query, args)
-  var L = pqnfields(res)
-  result = newRow(L)
-  if pqntuples(res) > 0:
-    setRow(res, result, 0, L)
-  pqclear(res)
-
-proc getRow*(db: DbConn, stmtName: SqlPrepared,
-             args: varargs[string, `$`]): Row {.tags: [ReadDbEffect].} =
-  var res = setupQuery(db, stmtName, args)
-  var L = pqNfields(res)
-  result = newRow(L)
-  if pqntuples(res) > 0:
-    setRow(res, result, 0, L)
-  pqClear(res)
-
-proc getAllRows*(db: DbConn, query: SqlQuery,
-                 args: varargs[string, `$`]): seq[Row] {.
-                 tags: [ReadDbEffect].} =
-  ## executes the query and returns the whole result dataset.
-  result = @[]
-  for r in fastRows(db, query, args):
-    result.add(r)
-
-proc getAllRows*(db: DbConn, stmtName: SqlPrepared,
-                 args: varargs[string, `$`]): seq[Row] {.tags:
-                 [ReadDbEffect].} =
-  ## executes the prepared query and returns the whole result dataset.
-  result = @[]
-  for r in fastRows(db, stmtName, args):
-    result.add(r)
-
-iterator rows*(db: DbConn, query: SqlQuery,
-               args: varargs[string, `$`]): Row {.tags: [ReadDbEffect].} =
-  ## same as `fastRows`, but slower and safe.
-  for r in items(getAllRows(db, query, args)): yield r
-
-iterator rows*(db: DbConn, stmtName: SqlPrepared,
-               args: varargs[string, `$`]): Row {.tags: [ReadDbEffect].} =
-  ## same as `fastRows`, but slower and safe.
-  for r in items(getAllRows(db, stmtName, args)): yield r
-
-proc getValue*(db: DbConn, query: SqlQuery,
-               args: varargs[string, `$`]): string {.
-               tags: [ReadDbEffect].} =
-  ## executes the query and returns the first column of the first row of the
-  ## result dataset. Returns "" if the dataset contains no rows or the database
-  ## value is NULL.
-  var res = setupQuery(db, query, args)
-  if pqntuples(res) > 0:
-    var x = pqgetvalue(res, 0, 0)
-    result = if isNil(x): "" else: $x
-  else:
-    result = ""
-
-proc getValue*(db: DbConn, stmtName: SqlPrepared,
-               args: varargs[string, `$`]): string {.
-               tags: [ReadDbEffect].} =
-  ## executes the query and returns the first column of the first row of the
-  ## result dataset. Returns "" if the dataset contains no rows or the database
-  ## value is NULL.
-  var res = setupQuery(db, stmtName, args)
-  if pqntuples(res) > 0:
-    var x = pqgetvalue(res, 0, 0)
-    result = if isNil(x): "" else: $x
-  else:
-    result = ""
-
-proc tryInsertID*(db: DbConn, query: SqlQuery,
-                  args: varargs[string, `$`]): int64 {.
-                  tags: [WriteDbEffect].}=
-  ## executes the query (typically "INSERT") and returns the
-  ## generated ID for the row or -1 in case of an error. For Postgre this adds
-  ## `RETURNING id` to the query, so it only works if your primary key is
-  ## named `id`.
-  var x = pqgetvalue(setupQuery(db, SqlQuery(string(query) & " RETURNING id"),
-    args), 0, 0)
-  if not isNil(x):
-    result = parseBiggestInt($x)
-  else:
-    result = -1
-
-proc insertID*(db: DbConn, query: SqlQuery,
-               args: varargs[string, `$`]): int64 {.
-               tags: [WriteDbEffect].} =
-  ## executes the query (typically "INSERT") and returns the
-  ## generated ID for the row. For Postgre this adds
-  ## `RETURNING id` to the query, so it only works if your primary key is
-  ## named `id`.
-  result = tryInsertID(db, query, args)
-  if result < 0: dbError(db)
-
-proc tryInsert*(db: DbConn, query: SqlQuery,pkName: string,
-                args: varargs[string, `$`]): int64
-               {.tags: [WriteDbEffect], since: (1, 3).}=
-  ## executes the query (typically "INSERT") and returns the
-  ## generated ID for the row or -1 in case of an error.
-  var x = pqgetvalue(setupQuery(db, SqlQuery(string(query) & " RETURNING " & pkName),
-    args), 0, 0)
-  if not isNil(x):
-    result = parseBiggestInt($x)
-  else:
-    result = -1
-
-proc insert*(db: DbConn, query: SqlQuery, pkName: string,
-             args: varargs[string, `$`]): int64
-            {.tags: [WriteDbEffect], since: (1, 3).} =
-  ## executes the query (typically "INSERT") and returns the
-  ## generated ID
-  result = tryInsertID(db, query, args)
-  if result < 0: dbError(db)
-
-proc execAffectedRows*(db: DbConn, query: SqlQuery,
-                       args: varargs[string, `$`]): int64 {.tags: [
-                       ReadDbEffect, WriteDbEffect].} =
-  ## executes the query (typically "UPDATE") and returns the
-  ## number of affected rows.
-  var q = dbFormat(query, args)
-  var res = pqExec(db, q)
-  if pqresultStatus(res) != PGRES_COMMAND_OK: dbError(db)
-  result = parseBiggestInt($pqcmdTuples(res))
-  pqclear(res)
-
-proc execAffectedRows*(db: DbConn, stmtName: SqlPrepared,
-                       args: varargs[string, `$`]): int64 {.tags: [
-                       ReadDbEffect, WriteDbEffect].} =
-  ## executes the query (typically "UPDATE") and returns the
-  ## number of affected rows.
-  var arr = allocCStringArray(args)
-  var res = pqexecPrepared(db, stmtName.string, int32(args.len), arr,
-                           nil, nil, 0)
-  deallocCStringArray(arr)
-  if pqresultStatus(res) != PGRES_COMMAND_OK: dbError(db)
-  result = parseBiggestInt($pqcmdTuples(res))
-  pqclear(res)
-
-proc close*(db: DbConn) {.tags: [DbEffect].} =
-  ## closes the database connection.
-  if db != nil: pqfinish(db)
-
-proc open*(connection, user, password, database: string): DbConn {.
-  tags: [DbEffect].} =
-  ## opens a database connection. Raises `EDb` if the connection could not
-  ## be established.
-  ##
-  ## Clients can also use Postgres keyword/value connection strings to
-  ## connect.
-  ##
-  ## Example:
-  ##
-  ## .. code-block:: nim
-  ##
-  ##      con = open("", "", "", "host=localhost port=5432 dbname=mydb")
-  ##
-  ## See http://www.postgresql.org/docs/current/static/libpq-connect.html#LIBPQ-CONNSTRING
-  ## for more information.
-  let
-    colonPos = connection.find(':')
-    host = if colonPos < 0: connection
-           else: substr(connection, 0, colonPos-1)
-    port = if colonPos < 0: ""
-           else: substr(connection, colonPos+1)
-  result = pqsetdbLogin(host, port, nil, nil, database, user, password)
-  if pqStatus(result) != CONNECTION_OK: dbError(result) # result = nil
-
-proc setEncoding*(connection: DbConn, encoding: string): bool {.
-  tags: [DbEffect].} =
-  ## sets the encoding of a database connection, returns true for
-  ## success, false for failure.
-  return pqsetClientEncoding(connection, encoding) == 0
-
-
-# Tests are in ../../tests/untestable/tpostgres.
diff --git a/lib/impure/db_sqlite.nim b/lib/impure/db_sqlite.nim
deleted file mode 100644
index 832407960..000000000
--- a/lib/impure/db_sqlite.nim
+++ /dev/null
@@ -1,950 +0,0 @@
-#
-#
-#            Nim's Runtime Library
-#        (c) Copyright 2015 Andreas Rumpf
-#
-#    See the file "copying.txt", included in this
-#    distribution, for details about the copyright.
-#
-
-## A higher level `SQLite`:idx: database wrapper. This interface
-## is implemented for other databases too.
-##
-## Basic usage
-## ===========
-##
-## The basic flow of using this module is:
-##
-## 1. Open database connection
-## 2. Execute SQL query
-## 3. Close database connection
-##
-## Parameter substitution
-## ----------------------
-##
-## All `db_*` modules support the same form of parameter substitution.
-## That is, using the `?` (question mark) to signify the place where a
-## value should be placed. For example:
-##
-## .. code-block:: Nim
-##
-##    sql"INSERT INTO my_table (colA, colB, colC) VALUES (?, ?, ?)"
-##
-## Opening a connection to a database
-## ----------------------------------
-##
-## .. code-block:: Nim
-##
-##    import std/db_sqlite
-##
-##    # user, password, database name can be empty.
-##    # These params are not used on db_sqlite module.
-##    let db = open("mytest.db", "", "", "")
-##    db.close()
-##
-## Creating a table
-## ----------------
-##
-## .. code-block:: Nim
-##
-##    db.exec(sql"DROP TABLE IF EXISTS my_table")
-##    db.exec(sql"""CREATE TABLE my_table (
-##                     id   INTEGER,
-##                     name VARCHAR(50) NOT NULL
-##                  )""")
-##
-## Inserting data
-## --------------
-##
-## .. code-block:: Nim
-##
-##    db.exec(sql"INSERT INTO my_table (id, name) VALUES (0, ?)",
-##            "Jack")
-##
-## Larger example
-## --------------
-##
-## .. code-block:: nim
-##
-##    import std/[db_sqlite, math]
-##
-##    let db = open("mytest.db", "", "", "")
-##
-##    db.exec(sql"DROP TABLE IF EXISTS my_table")
-##    db.exec(sql"""CREATE TABLE my_table (
-##                     id    INTEGER PRIMARY KEY,
-##                     name  VARCHAR(50) NOT NULL,
-##                     i     INT(11),
-##                     f     DECIMAL(18, 10)
-##                  )""")
-##
-##    db.exec(sql"BEGIN")
-##    for i in 1..1000:
-##      db.exec(sql"INSERT INTO my_table (name, i, f) VALUES (?, ?, ?)",
-##              "Item#" & $i, i, sqrt(i.float))
-##    db.exec(sql"COMMIT")
-##
-##    for x in db.fastRows(sql"SELECT * FROM my_table"):
-##      echo x
-##
-##    let id = db.tryInsertId(sql"""INSERT INTO my_table (name, i, f)
-##                                  VALUES (?, ?, ?)""",
-##                            "Item#1001", 1001, sqrt(1001.0))
-##    echo "Inserted item: ", db.getValue(sql"SELECT name FROM my_table WHERE id=?", id)
-##
-##    db.close()
-##
-## Storing binary data example
-##----------------------------
-##
-## .. code-block:: nim
-##
-##   import std/random
-##
-##   ## Generate random float datas
-##   var orig = newSeq[float64](150)
-##   randomize()
-##   for x in orig.mitems:
-##     x = rand(1.0)/10.0
-##
-##   let db = open("mysqlite.db", "", "", "")
-##   block: ## Create database
-##     ## Binary datas needs to be of type BLOB in SQLite
-##     let createTableStr = sql"""CREATE TABLE test(
-##       id INTEGER NOT NULL PRIMARY KEY,
-##       data BLOB
-##     )
-##     """
-##     db.exec(createTableStr)
-##
-##   block: ## Insert data
-##     var id = 1
-##     ## Data needs to be converted to seq[byte] to be interpreted as binary by bindParams
-##     var dbuf = newSeq[byte](orig.len*sizeof(float64))
-##     copyMem(unsafeAddr(dbuf[0]), unsafeAddr(orig[0]), dbuf.len)
-##
-##     ## Use prepared statement to insert binary data into database
-##     var insertStmt = db.prepare("INSERT INTO test (id, data) VALUES (?, ?)")
-##     insertStmt.bindParams(id, dbuf)
-##     let bres = db.tryExec(insertStmt)
-##     ## Check insert
-##     doAssert(bres)
-##     # Destroy statement
-##     finalize(insertStmt)
-##
-##   block: ## Use getValue to select data
-##     var dataTest = db.getValue(sql"SELECT data FROM test WHERE id = ?", 1)
-##     ## Calculate sequence size from buffer size
-##     let seqSize = int(dataTest.len*sizeof(byte)/sizeof(float64))
-##     ## Copy binary string data in dataTest into a seq
-##     var res: seq[float64] = newSeq[float64](seqSize)
-##     copyMem(unsafeAddr(res[0]), addr(dataTest[0]), dataTest.len)
-##
-##     ## Check datas obtained is identical
-##     doAssert res == orig
-##
-##   db.close()
-##
-##
-## Note
-## ====
-## This module does not implement any ORM features such as mapping the types from the schema.
-## Instead, a `seq[string]` is returned for each row.
-##
-## The reasoning is as follows:
-## 1. it's close to what many DBs offer natively (char**)
-## 2. it hides the number of types that the DB supports
-##    (int? int64? decimal up to 10 places? geo coords?)
-## 3. it's convenient when all you do is to forward the data to somewhere else (echo, log, put the data into a new query)
-##
-## See also
-## ========
-##
-## * `db_odbc module <db_odbc.html>`_ for ODBC database wrapper
-## * `db_mysql module <db_mysql.html>`_ for MySQL database wrapper
-## * `db_postgres module <db_postgres.html>`_ for PostgreSQL database wrapper
-
-{.experimental: "codeReordering".}
-
-import sqlite3, macros
-
-import db_common
-export db_common
-
-import std/private/since
-
-type
-  DbConn* = PSqlite3  ## Encapsulates a database connection.
-  Row* = seq[string]  ## A row of a dataset. `NULL` database values will be
-                      ## converted to an empty string.
-  InstantRow* = PStmt ## A handle that can be used to get a row's column
-                      ## text on demand.
-  SqlPrepared* = distinct PStmt ## a identifier for the prepared queries
-
-proc dbError*(db: DbConn) {.noreturn.} =
-  ## Raises a `DbError` exception.
-  ##
-  ## **Examples:**
-  ##
-  ## .. code-block:: Nim
-  ##
-  ##    let db = open("mytest.db", "", "", "")
-  ##    if not db.tryExec(sql"SELECT * FROM not_exist_table"):
-  ##      dbError(db)
-  ##    db.close()
-  var e: ref DbError
-  new(e)
-  e.msg = $sqlite3.errmsg(db)
-  raise e
-
-proc dbQuote*(s: string): string =
-  ## Escapes the `'` (single quote) char to `''`.
-  ## Because single quote is used for defining `VARCHAR` in SQL.
-  runnableExamples:
-    doAssert dbQuote("'") == "''''"
-    doAssert dbQuote("A Foobar's pen.") == "'A Foobar''s pen.'"
-
-  result = "'"
-  for c in items(s):
-    if c == '\'': add(result, "''")
-    else: add(result, c)
-  add(result, '\'')
-
-proc dbFormat(formatstr: SqlQuery, args: varargs[string]): string =
-  result = ""
-  var a = 0
-  for c in items(string(formatstr)):
-    if c == '?':
-      add(result, dbQuote(args[a]))
-      inc(a)
-    else:
-      add(result, c)
-
-proc prepare*(db: DbConn; q: string): SqlPrepared {.since: (1, 3).} =
-  ## Creates a new `SqlPrepared` statement.
-  if prepare_v2(db, q, q.len.cint,result.PStmt, nil) != SQLITE_OK:
-    discard finalize(result.PStmt)
-    dbError(db)
-
-proc tryExec*(db: DbConn, query: SqlQuery,
-              args: varargs[string, `$`]): bool {.
-              tags: [ReadDbEffect, WriteDbEffect].} =
-  ## Tries to execute the query and returns `true` if successful, `false` otherwise.
-  ##
-  ## **Examples:**
-  ##
-  ## .. code-block:: Nim
-  ##
-  ##    let db = open("mytest.db", "", "", "")
-  ##    if not db.tryExec(sql"SELECT * FROM my_table"):
-  ##      dbError(db)
-  ##    db.close()
-  assert(not db.isNil, "Database not connected.")
-  var q = dbFormat(query, args)
-  var stmt: sqlite3.PStmt
-  if prepare_v2(db, q, q.len.cint, stmt, nil) == SQLITE_OK:
-    let x = step(stmt)
-    if x in {SQLITE_DONE, SQLITE_ROW}:
-      result = finalize(stmt) == SQLITE_OK
-    else:
-      discard finalize(stmt)
-      result = false
-
-proc tryExec*(db: DbConn, stmtName: SqlPrepared): bool {.
-              tags: [ReadDbEffect, WriteDbEffect].} =
-    let x = step(stmtName.PStmt)
-    if x in {SQLITE_DONE, SQLITE_ROW}:
-      result = true
-    else:
-      discard finalize(stmtName.PStmt)
-      result = false
-
-proc exec*(db: DbConn, query: SqlQuery, args: varargs[string, `$`])  {.
-  tags: [ReadDbEffect, WriteDbEffect].} =
-  ## Executes the query and raises a `DbError` exception if not successful.
-  ##
-  ## **Examples:**
-  ##
-  ## .. code-block:: Nim
-  ##
-  ##    let db = open("mytest.db", "", "", "")
-  ##    try:
-  ##      db.exec(sql"INSERT INTO my_table (id, name) VALUES (?, ?)",
-  ##              1, "item#1")
-  ##    except:
-  ##      stderr.writeLine(getCurrentExceptionMsg())
-  ##    finally:
-  ##      db.close()
-  if not tryExec(db, query, args): dbError(db)
-
-proc newRow(L: int): Row =
-  newSeq(result, L)
-  for i in 0..L-1: result[i] = ""
-
-proc setupQuery(db: DbConn, query: SqlQuery,
-                args: varargs[string]): PStmt =
-  assert(not db.isNil, "Database not connected.")
-  var q = dbFormat(query, args)
-  if prepare_v2(db, q, q.len.cint, result, nil) != SQLITE_OK: dbError(db)
-
-proc setupQuery(db: DbConn, stmtName: SqlPrepared): SqlPrepared {.since: (1, 3).} =
-  assert(not db.isNil, "Database not connected.")
-  result = stmtName
-
-proc setRow(stmt: PStmt, r: var Row, cols: cint) =
-  for col in 0'i32..cols-1:
-    let cb = column_bytes(stmt, col)
-    setLen(r[col], cb) # set capacity
-    if column_type(stmt, col) == SQLITE_BLOB:
-      copyMem(addr(r[col][0]), column_blob(stmt, col), cb)
-    else:
-      setLen(r[col], 0)
-      let x = column_text(stmt, col)
-      if not isNil(x): add(r[col], x)
-
-iterator fastRows*(db: DbConn, query: SqlQuery,
-                   args: varargs[string, `$`]): Row {.tags: [ReadDbEffect].} =
-  ## Executes the query and iterates over the result dataset.
-  ##
-  ## This is very fast, but potentially dangerous. Use this iterator only
-  ## if you require **ALL** the rows.
-  ##
-  ## **Note:** Breaking the `fastRows()` iterator during a loop will cause the
-  ## next database query to raise a `DbError` exception `unable to close due
-  ## to ...`.
-  ##
-  ## **Examples:**
-  ##
-  ## .. code-block:: Nim
-  ##
-  ##    let db = open("mytest.db", "", "", "")
-  ##
-  ##    # Records of my_table:
-  ##    # | id | name     |
-  ##    # |----|----------|
-  ##    # |  1 | item#1   |
-  ##    # |  2 | item#2   |
-  ##
-  ##    for row in db.fastRows(sql"SELECT id, name FROM my_table"):
-  ##      echo row
-  ##
-  ##    # Output:
-  ##    # @["1", "item#1"]
-  ##    # @["2", "item#2"]
-  ##
-  ##    db.close()
-  var stmt = setupQuery(db, query, args)
-  var L = (column_count(stmt))
-  var result = newRow(L)
-  try:
-    while step(stmt) == SQLITE_ROW:
-      setRow(stmt, result, L)
-      yield result
-  finally:
-    if finalize(stmt) != SQLITE_OK: dbError(db)
-
-iterator fastRows*(db: DbConn, stmtName: SqlPrepared): Row
-                  {.tags: [ReadDbEffect,WriteDbEffect], since: (1, 3).} =
-  discard setupQuery(db, stmtName)
-  var L = (column_count(stmtName.PStmt))
-  var result = newRow(L)
-  try:
-    while step(stmtName.PStmt) == SQLITE_ROW:
-      setRow(stmtName.PStmt, result, L)
-      yield result
-  except:
-    dbError(db)
-
-iterator instantRows*(db: DbConn, query: SqlQuery,
-                      args: varargs[string, `$`]): InstantRow
-                      {.tags: [ReadDbEffect].} =
-  ## Similar to `fastRows iterator <#fastRows.i,DbConn,SqlQuery,varargs[string,]>`_
-  ## but returns a handle that can be used to get column text
-  ## on demand using `[]`. Returned handle is valid only within the iterator body.
-  ##
-  ## **Examples:**
-  ##
-  ## .. code-block:: Nim
-  ##
-  ##    let db = open("mytest.db", "", "", "")
-  ##
-  ##    # Records of my_table:
-  ##    # | id | name     |
-  ##    # |----|----------|
-  ##    # |  1 | item#1   |
-  ##    # |  2 | item#2   |
-  ##
-  ##    for row in db.instantRows(sql"SELECT * FROM my_table"):
-  ##      echo "id:" & row[0]
-  ##      echo "name:" & row[1]
-  ##      echo "length:" & $len(row)
-  ##
-  ##    # Output:
-  ##    # id:1
-  ##    # name:item#1
-  ##    # length:2
-  ##    # id:2
-  ##    # name:item#2
-  ##    # length:2
-  ##
-  ##    db.close()
-  var stmt = setupQuery(db, query, args)
-  try:
-    while step(stmt) == SQLITE_ROW:
-      yield stmt
-  finally:
-    if finalize(stmt) != SQLITE_OK: dbError(db)
-
-iterator instantRows*(db: DbConn, stmtName: SqlPrepared): InstantRow
-                      {.tags: [ReadDbEffect,WriteDbEffect], since: (1, 3).} =
-  var stmt = setupQuery(db, stmtName).PStmt
-  try:
-    while step(stmt) == SQLITE_ROW:
-      yield stmt
-  except:
-    dbError(db)
-
-proc toTypeKind(t: var DbType; x: int32) =
-  case x
-  of SQLITE_INTEGER:
-    t.kind = dbInt
-    t.size = 8
-  of SQLITE_FLOAT:
-    t.kind = dbFloat
-    t.size = 8
-  of SQLITE_BLOB: t.kind = dbBlob
-  of SQLITE_NULL: t.kind = dbNull
-  of SQLITE_TEXT: t.kind = dbVarchar
-  else: t.kind = dbUnknown
-
-proc setColumns(columns: var DbColumns; x: PStmt) =
-  let L = column_count(x)
-  setLen(columns, L)
-  for i in 0'i32 ..< L:
-    columns[i].name = $column_name(x, i)
-    columns[i].typ.name = $column_decltype(x, i)
-    toTypeKind(columns[i].typ, column_type(x, i))
-    columns[i].tableName = $column_table_name(x, i)
-
-iterator instantRows*(db: DbConn; columns: var DbColumns; query: SqlQuery,
-                      args: varargs[string, `$`]): InstantRow
-                      {.tags: [ReadDbEffect].} =
-  ## Similar to `instantRows iterator <#instantRows.i,DbConn,SqlQuery,varargs[string,]>`_,
-  ## but sets information about columns to `columns`.
-  ##
-  ## **Examples:**
-  ##
-  ## .. code-block:: Nim
-  ##
-  ##    let db = open("mytest.db", "", "", "")
-  ##
-  ##    # Records of my_table:
-  ##    # | id | name     |
-  ##    # |----|----------|
-  ##    # |  1 | item#1   |
-  ##    # |  2 | item#2   |
-  ##
-  ##    var columns: DbColumns
-  ##    for row in db.instantRows(columns, sql"SELECT * FROM my_table"):
-  ##      discard
-  ##    echo columns[0]
-  ##
-  ##    # Output:
-  ##    # (name: "id", tableName: "my_table", typ: (kind: dbNull,
-  ##    # notNull: false, name: "INTEGER", size: 0, maxReprLen: 0, precision: 0,
-  ##    # scale: 0, min: 0, max: 0, validValues: @[]), primaryKey: false,
-  ##    # foreignKey: false)
-  ##
-  ##    db.close()
-  var stmt = setupQuery(db, query, args)
-  setColumns(columns, stmt)
-  try:
-    while step(stmt) == SQLITE_ROW:
-      yield stmt
-  finally:
-    if finalize(stmt) != SQLITE_OK: dbError(db)
-
-proc `[]`*(row: InstantRow, col: int32): string {.inline.} =
-  ## Returns text for given column of the row.
-  ##
-  ## See also:
-  ## * `instantRows iterator <#instantRows.i,DbConn,SqlQuery,varargs[string,]>`_
-  ##   example code
-  $column_text(row, col)
-
-proc unsafeColumnAt*(row: InstantRow, index: int32): cstring {.inline.} =
-  ## Returns cstring for given column of the row.
-  ##
-  ## See also:
-  ## * `instantRows iterator <#instantRows.i,DbConn,SqlQuery,varargs[string,]>`_
-  ##   example code
-  column_text(row, index)
-
-proc len*(row: InstantRow): int32 {.inline.} =
-  ## Returns number of columns in a row.
-  ##
-  ## See also:
-  ## * `instantRows iterator <#instantRows.i,DbConn,SqlQuery,varargs[string,]>`_
-  ##   example code
-  column_count(row)
-
-proc getRow*(db: DbConn, query: SqlQuery,
-             args: varargs[string, `$`]): Row {.tags: [ReadDbEffect].} =
-  ## Retrieves a single row. If the query doesn't return any rows, this proc
-  ## will return a `Row` with empty strings for each column.
-  ##
-  ## **Examples:**
-  ##
-  ## .. code-block:: Nim
-  ##
-  ##    let db = open("mytest.db", "", "", "")
-  ##
-  ##    # Records of my_table:
-  ##    # | id | name     |
-  ##    # |----|----------|
-  ##    # |  1 | item#1   |
-  ##    # |  2 | item#2   |
-  ##
-  ##    doAssert db.getRow(sql"SELECT id, name FROM my_table"
-  ##                       ) == Row(@["1", "item#1"])
-  ##    doAssert db.getRow(sql"SELECT id, name FROM my_table WHERE id = ?",
-  ##                       2) == Row(@["2", "item#2"])
-  ##
-  ##    # Returns empty.
-  ##    doAssert db.getRow(sql"INSERT INTO my_table (id, name) VALUES (?, ?)",
-  ##                       3, "item#3") == @[]
-  ##    doAssert db.getRow(sql"DELETE FROM my_table WHERE id = ?", 3) == @[]
-  ##    doAssert db.getRow(sql"UPDATE my_table SET name = 'ITEM#1' WHERE id = ?",
-  ##                       1) == @[]
-  ##    db.close()
-  var stmt = setupQuery(db, query, args)
-  var L = (column_count(stmt))
-  result = newRow(L)
-  if step(stmt) == SQLITE_ROW:
-    setRow(stmt, result, L)
-  if finalize(stmt) != SQLITE_OK: dbError(db)
-
-proc getAllRows*(db: DbConn, query: SqlQuery,
-                 args: varargs[string, `$`]): seq[Row] {.tags: [ReadDbEffect].} =
-  ## Executes the query and returns the whole result dataset.
-  ##
-  ## **Examples:**
-  ##
-  ## .. code-block:: Nim
-  ##
-  ##    let db = open("mytest.db", "", "", "")
-  ##
-  ##    # Records of my_table:
-  ##    # | id | name     |
-  ##    # |----|----------|
-  ##    # |  1 | item#1   |
-  ##    # |  2 | item#2   |
-  ##
-  ##    doAssert db.getAllRows(sql"SELECT id, name FROM my_table") == @[Row(@["1", "item#1"]), Row(@["2", "item#2"])]
-  ##    db.close()
-  result = @[]
-  for r in fastRows(db, query, args):
-    result.add(r)
-
-proc getAllRows*(db: DbConn, stmtName: SqlPrepared): seq[Row]
-                {.tags: [ReadDbEffect,WriteDbEffect], since: (1, 3).} =
-  result = @[]
-  for r in fastRows(db, stmtName):
-    result.add(r)
-
-iterator rows*(db: DbConn, query: SqlQuery,
-               args: varargs[string, `$`]): Row {.tags: [ReadDbEffect].} =
-  ## Similar to `fastRows iterator <#fastRows.i,DbConn,SqlQuery,varargs[string,]>`_,
-  ## but slower and safe.
-  ##
-  ## **Examples:**
-  ##
-  ## .. code-block:: Nim
-  ##
-  ##    let db = open("mytest.db", "", "", "")
-  ##
-  ##    # Records of my_table:
-  ##    # | id | name     |
-  ##    # |----|----------|
-  ##    # |  1 | item#1   |
-  ##    # |  2 | item#2   |
-  ##
-  ##    for row in db.rows(sql"SELECT id, name FROM my_table"):
-  ##      echo row
-  ##
-  ##    ## Output:
-  ##    ## @["1", "item#1"]
-  ##    ## @["2", "item#2"]
-  ##
-  ##    db.close()
-  for r in fastRows(db, query, args): yield r
-
-iterator rows*(db: DbConn, stmtName: SqlPrepared): Row
-              {.tags: [ReadDbEffect,WriteDbEffect], since: (1, 3).} =
-  for r in fastRows(db, stmtName): yield r
-
-proc getValue*(db: DbConn, query: SqlQuery,
-               args: varargs[string, `$`]): string {.tags: [ReadDbEffect].} =
-  ## Executes the query and returns the first column of the first row of the
-  ## result dataset. Returns `""` if the dataset contains no rows or the database
-  ## value is `NULL`.
-  ##
-  ## **Examples:**
-  ##
-  ## .. code-block:: Nim
-  ##
-  ##    let db = open("mytest.db", "", "", "")
-  ##
-  ##    # Records of my_table:
-  ##    # | id | name     |
-  ##    # |----|----------|
-  ##    # |  1 | item#1   |
-  ##    # |  2 | item#2   |
-  ##
-  ##    doAssert db.getValue(sql"SELECT name FROM my_table WHERE id = ?",
-  ##                         2) == "item#2"
-  ##    doAssert db.getValue(sql"SELECT id, name FROM my_table") == "1"
-  ##    doAssert db.getValue(sql"SELECT name, id FROM my_table") == "item#1"
-  ##
-  ##    db.close()
-  var stmt = setupQuery(db, query, args)
-  if step(stmt) == SQLITE_ROW:
-    let cb = column_bytes(stmt, 0)
-    if cb == 0:
-      result = ""
-    else:
-      if column_type(stmt, 0) == SQLITE_BLOB:
-        result.setLen(cb)
-        copyMem(addr(result[0]), column_blob(stmt, 0), cb)
-      else:
-        result = newStringOfCap(cb)
-        add(result, column_text(stmt, 0))
-  else:
-    result = ""
-  if finalize(stmt) != SQLITE_OK: dbError(db)
-
-proc getValue*(db: DbConn,  stmtName: SqlPrepared): string
-              {.tags: [ReadDbEffect,WriteDbEffect], since: (1, 3).} =
-  var stmt = setupQuery(db, stmtName).PStmt
-  if step(stmt) == SQLITE_ROW:
-    let cb = column_bytes(stmt, 0)
-    if cb == 0:
-      result = ""
-    else:
-      if column_type(stmt, 0) == SQLITE_BLOB:
-        result.setLen(cb)
-        copyMem(addr(result[0]), column_blob(stmt, 0), cb)
-      else:
-        result = newStringOfCap(cb)
-        add(result, column_text(stmt, 0))
-  else:
-    result = ""
-
-proc tryInsertID*(db: DbConn, query: SqlQuery,
-                  args: varargs[string, `$`]): int64
-                  {.tags: [WriteDbEffect], raises: [].} =
-  ## Executes the query (typically "INSERT") and returns the
-  ## generated ID for the row or -1 in case of an error.
-  ##
-  ## **Examples:**
-  ##
-  ## .. code-block:: Nim
-  ##
-  ##    let db = open("mytest.db", "", "", "")
-  ##    db.exec(sql"CREATE TABLE my_table (id INTEGER, name VARCHAR(50) NOT NULL)")
-  ##
-  ##    doAssert db.tryInsertID(sql"INSERT INTO not_exist_table (id, name) VALUES (?, ?)",
-  ##                            1, "item#1") == -1
-  ##    db.close()
-  assert(not db.isNil, "Database not connected.")
-  var q = dbFormat(query, args)
-  var stmt: sqlite3.PStmt
-  result = -1
-  if prepare_v2(db, q, q.len.cint, stmt, nil) == SQLITE_OK:
-    if step(stmt) == SQLITE_DONE:
-      result = last_insert_rowid(db)
-    if finalize(stmt) != SQLITE_OK:
-      result = -1
-  else:
-    discard finalize(stmt)
-
-proc insertID*(db: DbConn, query: SqlQuery,
-               args: varargs[string, `$`]): int64 {.tags: [WriteDbEffect].} =
-  ## Executes the query (typically "INSERT") and returns the
-  ## generated ID for the row.
-  ##
-  ## Raises a `DbError` exception when failed to insert row.
-  ## For Postgre this adds `RETURNING id` to the query, so it only works
-  ## if your primary key is named `id`.
-  ##
-  ## **Examples:**
-  ##
-  ## .. code-block:: Nim
-  ##
-  ##    let db = open("mytest.db", "", "", "")
-  ##    db.exec(sql"CREATE TABLE my_table (id INTEGER, name VARCHAR(50) NOT NULL)")
-  ##
-  ##    for i in 0..2:
-  ##      let id = db.insertID(sql"INSERT INTO my_table (id, name) VALUES (?, ?)", i, "item#" & $i)
-  ##      echo "LoopIndex = ", i, ", InsertID = ", id
-  ##
-  ##    # Output:
-  ##    # LoopIndex = 0, InsertID = 1
-  ##    # LoopIndex = 1, InsertID = 2
-  ##    # LoopIndex = 2, InsertID = 3
-  ##
-  ##    db.close()
-  result = tryInsertID(db, query, args)
-  if result < 0: dbError(db)
-
-proc tryInsert*(db: DbConn, query: SqlQuery, pkName: string,
-                args: varargs[string, `$`]): int64
-               {.tags: [WriteDbEffect], raises: [], since: (1, 3).} =
-  ## same as tryInsertID
-  tryInsertID(db, query, args)
-
-proc insert*(db: DbConn, query: SqlQuery, pkName: string,
-             args: varargs[string, `$`]): int64
-            {.tags: [WriteDbEffect], since: (1, 3).} =
-  ## same as insertId
-  result = tryInsert(db, query,pkName, args)
-  if result < 0: dbError(db)
-
-proc execAffectedRows*(db: DbConn, query: SqlQuery,
-                       args: varargs[string, `$`]): int64 {.
-                       tags: [ReadDbEffect, WriteDbEffect].} =
-  ## Executes the query (typically "UPDATE") and returns the
-  ## number of affected rows.
-  ##
-  ## **Examples:**
-  ##
-  ## .. code-block:: Nim
-  ##
-  ##    let db = open("mytest.db", "", "", "")
-  ##
-  ##    # Records of my_table:
-  ##    # | id | name     |
-  ##    # |----|----------|
-  ##    # |  1 | item#1   |
-  ##    # |  2 | item#2   |
-  ##
-  ##    doAssert db.execAffectedRows(sql"UPDATE my_table SET name = 'TEST'") == 2
-  ##
-  ##    db.close()
-  exec(db, query, args)
-  result = changes(db)
-
-proc execAffectedRows*(db: DbConn, stmtName: SqlPrepared): int64
-                      {.tags: [ReadDbEffect, WriteDbEffect],since: (1, 3).} =
-  exec(db, stmtName)
-  result = changes(db)
-
-proc close*(db: DbConn) {.tags: [DbEffect].} =
-  ## Closes the database connection.
-  ##
-  ## **Examples:**
-  ##
-  ## .. code-block:: Nim
-  ##
-  ##    let db = open("mytest.db", "", "", "")
-  ##    db.close()
-  if sqlite3.close(db) != SQLITE_OK: dbError(db)
-
-proc open*(connection, user, password, database: string): DbConn {.
-  tags: [DbEffect].} =
-  ## Opens a database connection. Raises a `DbError` exception if the connection
-  ## could not be established.
-  ##
-  ## **Note:** Only the `connection` parameter is used for `sqlite`.
-  ##
-  ## **Examples:**
-  ##
-  ## .. code-block:: Nim
-  ##
-  ##    try:
-  ##      let db = open("mytest.db", "", "", "")
-  ##      ## do something...
-  ##      ## db.getAllRows(sql"SELECT * FROM my_table")
-  ##      db.close()
-  ##    except:
-  ##      stderr.writeLine(getCurrentExceptionMsg())
-  var db: DbConn
-  if sqlite3.open(connection, db) == SQLITE_OK:
-    result = db
-  else:
-    dbError(db)
-
-proc setEncoding*(connection: DbConn, encoding: string): bool {.
-  tags: [DbEffect].} =
-  ## Sets the encoding of a database connection, returns `true` for
-  ## success, `false` for failure.
-  ##
-  ## **Note:** The encoding cannot be changed once it's been set.
-  ## According to SQLite3 documentation, any attempt to change
-  ## the encoding after the database is created will be silently
-  ## ignored.
-  exec(connection, sql"PRAGMA encoding = ?", [encoding])
-  result = connection.getValue(sql"PRAGMA encoding") == encoding
-
-proc finalize*(sqlPrepared:SqlPrepared) {.discardable, since: (1, 3).} =
-  discard finalize(sqlPrepared.PStmt)
-
-template dbBindParamError*(paramIdx: int, val: varargs[untyped]) =
-  ## Raises a `DbError` exception.
-  var e: ref DbError
-  new(e)
-  e.msg = "error binding param in position " & $paramIdx
-  raise e
-
-proc bindParam*(ps: SqlPrepared, paramIdx: int, val: int32) {.since: (1, 3).} =
-  ## Binds a int32  to the specified paramIndex.
-  if bind_int(ps.PStmt, paramIdx.int32, val) != SQLITE_OK:
-    dbBindParamError(paramIdx, val)
-
-proc bindParam*(ps: SqlPrepared, paramIdx: int, val: int64) {.since: (1, 3).} =
-  ## Binds a int64  to the specified paramIndex.
-  if bind_int64(ps.PStmt, paramIdx.int32, val) != SQLITE_OK:
-    dbBindParamError(paramIdx, val)
-
-proc bindParam*(ps: SqlPrepared, paramIdx: int, val: int) {.since: (1, 3).} =
-  ## Binds a int  to the specified paramIndex.
-  when sizeof(int) == 8:
-    bindParam(ps, paramIdx, val.int64)
-  else:
-    bindParam(ps, paramIdx, val.int32)
-
-proc bindParam*(ps: SqlPrepared, paramIdx: int, val: float64) {.since: (1, 3).} =
-  ## Binds a 64bit float to the specified paramIndex.
-  if bind_double(ps.PStmt, paramIdx.int32, val) != SQLITE_OK:
-    dbBindParamError(paramIdx, val)
-
-proc bindNull*(ps: SqlPrepared, paramIdx: int) {.since: (1, 3).} =
-  ## Sets the bindparam at the specified paramIndex to null
-  ## (default behaviour by sqlite).
-  if bind_null(ps.PStmt, paramIdx.int32) != SQLITE_OK:
-    dbBindParamError(paramIdx)
-
-proc bindParam*(ps: SqlPrepared, paramIdx: int, val: string, copy = true) {.since: (1, 3).} =
-  ## Binds a string to the specified paramIndex.
-  ## if copy is true then SQLite makes its own private copy of the data immediately
-  if bind_text(ps.PStmt, paramIdx.int32, val.cstring, val.len.int32, if copy: SQLITE_TRANSIENT else: SQLITE_STATIC) != SQLITE_OK:
-    dbBindParamError(paramIdx, val)
-
-proc bindParam*(ps: SqlPrepared, paramIdx: int,val: openArray[byte], copy = true) {.since: (1, 3).} =
-  ## binds a blob to the specified paramIndex.
-  ## if copy is true then SQLite makes its own private copy of the data immediately
-  let len = val.len
-  if bind_blob(ps.PStmt, paramIdx.int32, val[0].unsafeAddr, len.int32, if copy: SQLITE_TRANSIENT else: SQLITE_STATIC) != SQLITE_OK:
-    dbBindParamError(paramIdx, val)
-
-macro bindParams*(ps: SqlPrepared, params: varargs[untyped]): untyped {.since: (1, 3).} =
-  let bindParam = bindSym("bindParam", brOpen)
-  let bindNull = bindSym("bindNull")
-  let preparedStatement = genSym()
-  result = newStmtList()
-  # Store `ps` in a temporary variable. This prevents `ps` from being evaluated every call.
-  result.add newNimNode(nnkLetSection).add(newIdentDefs(preparedStatement, newEmptyNode(), ps))
-  for idx, param in params:
-    if param.kind != nnkNilLit:
-      result.add newCall(bindParam, preparedStatement, newIntLitNode idx + 1, param)
-    else:
-      result.add newCall(bindNull, preparedStatement, newIntLitNode idx + 1)
-
-macro untypedLen(args: varargs[untyped]): int =
-  newLit(args.len)
-
-template exec*(db: DbConn, stmtName: SqlPrepared,
-          args: varargs[typed]): untyped =
-  when untypedLen(args) > 0:
-    if reset(stmtName.PStmt) != SQLITE_OK:
-      dbError(db)
-    if clear_bindings(stmtName.PStmt) != SQLITE_OK:
-      dbError(db)
-    stmtName.bindParams(args)
-  if not tryExec(db, stmtName): dbError(db)
-
-when not defined(testing) and isMainModule:
-  var db = open(":memory:", "", "", "")
-  exec(db, sql"create table tbl1(one varchar(10), two smallint)", [])
-  exec(db, sql"insert into tbl1 values('hello!',10)", [])
-  exec(db, sql"insert into tbl1 values('goodbye', 20)", [])
-  var p1 = db.prepare "create table tbl2(one varchar(10), two smallint)"
-  exec(db, p1)
-  finalize(p1)
-  var p2 = db.prepare "insert into tbl2 values('hello!',10)"
-  exec(db, p2)
-  finalize(p2)
-  var p3 = db.prepare "insert into tbl2 values('goodbye', 20)"
-  exec(db, p3)
-  finalize(p3)
-  #db.query("create table tbl1(one varchar(10), two smallint)")
-  #db.query("insert into tbl1 values('hello!',10)")
-  #db.query("insert into tbl1 values('goodbye', 20)")
-  for r in db.rows(sql"select * from tbl1", []):
-    echo(r[0], r[1])
-  for r in db.instantRows(sql"select * from tbl1", []):
-    echo(r[0], r[1])
-  var p4 =  db.prepare "select * from tbl2"
-  for r in db.rows(p4):
-    echo(r[0], r[1])
-  finalize(p4)
-  var i5 = 0
-  var p5 =  db.prepare "select * from tbl2"
-  for r in db.instantRows(p5):
-    inc i5
-    echo(r[0], r[1])
-  assert i5 == 2
-  finalize(p5)
-
-  for r in db.rows(sql"select * from tbl2", []):
-    echo(r[0], r[1])
-  for r in db.instantRows(sql"select * from tbl2", []):
-    echo(r[0], r[1])
-  var p6 = db.prepare "select * from tbl2 where one = ? "
-  p6.bindParams("goodbye")
-  var rowsP3 = 0
-  for r in db.rows(p6):
-    rowsP3 = 1
-    echo(r[0], r[1])
-  assert rowsP3 == 1
-  finalize(p6)
-
-  var p7 = db.prepare "select * from tbl2 where two=?"
-  p7.bindParams(20'i32)
-  when sizeof(int) == 4:
-    p7.bindParams(20)
-  var rowsP = 0
-  for r in db.rows(p7):
-    rowsP = 1
-    echo(r[0], r[1])
-  assert rowsP == 1
-  finalize(p7)
-
-  exec(db, sql"CREATE TABLE photos(ID INTEGER PRIMARY KEY AUTOINCREMENT, photo BLOB)")
-  var p8 = db.prepare "INSERT INTO photos (ID,PHOTO) VALUES (?,?)"
-  var d = "abcdefghijklmnopqrstuvwxyz"
-  p8.bindParams(1'i32, "abcdefghijklmnopqrstuvwxyz")
-  exec(db, p8)
-  finalize(p8)
-  var p10 = db.prepare "INSERT INTO photos (ID,PHOTO) VALUES (?,?)"
-  p10.bindParams(2'i32,nil)
-  exec(db, p10)
-  exec( db, p10, 3, nil)
-  finalize(p10)
-  for r in db.rows(sql"select * from photos where ID = 1", []):
-    assert r[1].len == d.len
-    assert r[1] == d
-  var i6 = 0
-  for r in db.rows(sql"select * from photos where ID = 3", []):
-    i6 = 1
-  assert i6 == 1
-  var p9 = db.prepare("select * from photos where PHOTO is ?")
-  p9.bindParams(nil)
-  var rowsP2 = 0
-  for r in db.rows(p9):
-    rowsP2 = 1
-    echo(r[0], repr r[1])
-  assert rowsP2 == 1
-  finalize(p9)
-
-  db_sqlite.close(db)
diff --git a/lib/impure/nre.nim b/lib/impure/nre.nim
index 7b2d7d3ee..39d238055 100644
--- a/lib/impure/nre.nim
+++ b/lib/impure/nre.nim
@@ -20,15 +20,17 @@ when defined(js):
 ## search the internet for a wide variety of third-party documentation and
 ## tools.
 ##
-## **Note**: If you love `sequtils.toSeq` we have bad news for you. This
-## library doesn't work with it due to documented compiler limitations. As
-## a workaround, use this:
-##
-## .. code-block:: nim
-##
-##    import std/nre except toSeq
-##
-##
+## .. warning:: If you love `sequtils.toSeq` we have bad news for you. This
+##   library doesn't work with it due to documented compiler limitations. As
+##   a workaround, use this:
+runnableExamples:
+  # either `import std/nre except toSeq` or fully qualify `sequtils.toSeq`:
+  import std/sequtils
+  iterator iota(n: int): int =
+    for i in 0..<n: yield i
+  assert sequtils.toSeq(iota(3)) == @[0, 1, 2]
+## .. note:: There are also alternative nimble packages such as [tinyre](https://github.com/khchen/tinyre)
+##   and [regex](https://github.com/nitely/nim-regex).
 ## Licencing
 ## ---------
 ##
@@ -36,40 +38,38 @@ when defined(js):
 ## this module.
 ##
 ## .. _`some additional terms`: http://pcre.sourceforge.net/license.txt
-##
 runnableExamples:
+  import std/sugar
   let vowels = re"[aeoui]"
-
-  let expectedResults = [
-    1 .. 1,
-    2 .. 2,
-    4 .. 4,
-    6 .. 6,
-    7 .. 7,
-  ]
-  var i = 0
-  for match in "moigagoo".findIter(vowels):
-    doAssert match.matchBounds == expectedResults[i]
-    inc i
+  let bounds = collect:
+    for match in "moiga".findIter(vowels): match.matchBounds
+  assert bounds == @[1 .. 1, 2 .. 2, 4 .. 4]
+  from std/sequtils import toSeq
+  let s = sequtils.toSeq("moiga".findIter(vowels))
+    # fully qualified to avoid confusion with nre.toSeq
+  assert s.len == 3
 
   let firstVowel = "foo".find(vowels)
   let hasVowel = firstVowel.isSome()
-  if hasVowel:
-    let matchBounds = firstVowel.get().captureBounds[-1]
-    doAssert matchBounds.a == 1
+  assert hasVowel
+  let matchBounds = firstVowel.get().captureBounds[-1]
+  assert matchBounds.a == 1
 
-  ## as with module `re`, unless specified otherwise, `start` parameter in each
-  ## proc indicates where the scan starts, but outputs are relative to the start
-  ## of the input string, not to `start`:
-  doAssert find("uxabc", re"(?<=x|y)ab", start = 1).get.captures[-1] == "ab"
-  doAssert find("uxabc", re"ab", start = 3).isNone
+  # as with module `re`, unless specified otherwise, `start` parameter in each
+  # proc indicates where the scan starts, but outputs are relative to the start
+  # of the input string, not to `start`:
+  assert find("uxabc", re"(?<=x|y)ab", start = 1).get.captures[-1] == "ab"
+  assert find("uxabc", re"ab", start = 3).isNone
 
-from pcre import nil
+from std/pcre import nil
 import nre/private/util
-import tables
-from strutils import `%`
-import options
-from unicode import runeLenAt
+import std/tables
+from std/strutils import `%`
+import std/options
+from std/unicode import runeLenAt
+
+when defined(nimPreviewSlimSystem):
+  import std/assertions
 
 export options
 
@@ -80,16 +80,16 @@ type
     ## comment".`
     ##
     ## `pattern: string`
-    ##     the string that was used to create the pattern. For details on how
+    ## :   the string that was used to create the pattern. For details on how
     ##     to write a pattern, please see `the official PCRE pattern
     ##     documentation.
     ##     <https://www.pcre.org/original/doc/html/pcrepattern.html>`_
     ##
     ## `captureCount: int`
-    ##     the number of captures that the pattern has.
+    ## :   the number of captures that the pattern has.
     ##
     ## `captureNameId: Table[string, int]`
-    ##     a table from the capture names to their numeric id.
+    ## :   a table from the capture names to their numeric id.
     ##
     ##
     ## Options
@@ -145,7 +145,7 @@ type
     ## `DOLLAR_ENDONLY`, `FIRSTLINE`, `NO_AUTO_CAPTURE`,
     ## `JAVASCRIPT_COMPAT`, `U`, `NO_STUDY`. In other PCRE wrappers, you
     ## will need to pass these as separate flags to PCRE.
-    pattern*: string  ## not nil
+    pattern*: string
     pcreObj: ptr pcre.Pcre  ## not nil
     pcreExtra: ptr pcre.ExtraData  ## nil
 
@@ -156,49 +156,39 @@ type
     ## execution. On failure, it is none, on success, it is some.
     ##
     ## `pattern: Regex`
-    ##     the pattern that is being matched
+    ## :   the pattern that is being matched
     ##
     ## `str: string`
-    ##     the string that was matched against
+    ## :   the string that was matched against
     ##
     ## `captures[]: string`
-    ##     the string value of whatever was captured at that id. If the value
+    ## :   the string value of whatever was captured at that id. If the value
     ##     is invalid, then behavior is undefined. If the id is `-1`, then
     ##     the whole match is returned. If the given capture was not matched,
-    ##     `nil` is returned.
-    ##
-    ##     -  `"abc".match(re"(\w)").get.captures[0] == "a"`
-    ##     -  `"abc".match(re"(?<letter>\w)").get.captures["letter"] == "a"`
-    ##     -  `"abc".match(re"(\w)\w").get.captures[-1] == "ab"`
+    ##     `nil` is returned. See examples for `match`.
     ##
     ## `captureBounds[]: HSlice[int, int]`
-    ##     gets the bounds of the given capture according to the same rules as
+    ## :   gets the bounds of the given capture according to the same rules as
     ##     the above. If the capture is not filled, then `None` is returned.
-    ##     The bounds are both inclusive.
-    ##
-    ##     -  `"abc".match(re"(\w)").get.captureBounds[0] == 0 .. 0`
-    ##     -  `0 in "abc".match(re"(\w)").get.captureBounds == true`
-    ##     -  `"abc".match(re"").get.captureBounds[-1] == 0 .. -1`
-    ##     -  `"abc".match(re"abc").get.captureBounds[-1] == 0 .. 2`
+    ##     The bounds are both inclusive.  See examples for `match`.
     ##
     ## `match: string`
-    ##     the full text of the match.
+    ## :   the full text of the match.
     ##
     ## `matchBounds: HSlice[int, int]`
-    ##     the bounds of the match, as in `captureBounds[]`
+    ## :   the bounds of the match, as in `captureBounds[]`
     ##
     ## `(captureBounds|captures).toTable`
-    ##     returns a table with each named capture as a key.
+    ## :   returns a table with each named capture as a key.
     ##
     ## `(captureBounds|captures).toSeq`
-    ##     returns all the captures by their number.
+    ## :   returns all the captures by their number.
     ##
     ## `$: string`
-    ##     same as `match`
+    ## :   same as `match`
     pattern*: Regex  ## The regex doing the matching.
                      ## Not nil.
     str*: string  ## The string that was matched against.
-                  ## Not nil.
     pcreMatchBounds: seq[HSlice[cint, cint]] ## First item is the bounds of the match
                                             ## Other items are the captures
                                             ## `a` is inclusive start, `b` is exclusive end
@@ -226,22 +216,12 @@ type
     ## for whatever reason. The message contains the error
     ## code.
 
-runnableExamples:
-  # This MUST be kept in sync with the examples in RegexMatch
-  doAssert "abc".match(re"(\w)").get.captures[0] == "a"
-  doAssert "abc".match(re"(?<letter>\w)").get.captures["letter"] == "a"
-  doAssert "abc".match(re"(\w)\w").get.captures[-1] == "ab"
-
-  doAssert "abc".match(re"(\w)").get.captureBounds[0] == 0 .. 0
-  doAssert 0 in "abc".match(re"(\w)").get.captureBounds == true
-  doAssert "abc".match(re"").get.captureBounds[-1] == 0 .. -1
-  doAssert "abc".match(re"abc").get.captureBounds[-1] == 0 .. 2
-
-
 proc destroyRegex(pattern: Regex) =
+  `=destroy`(pattern.pattern)
   pcre.free_substring(cast[cstring](pattern.pcreObj))
   if pattern.pcreExtra != nil:
     pcre.free_study(pattern.pcreExtra)
+  `=destroy`(pattern.captureNameToId)
 
 proc getinfo[T](pattern: Regex, opt: cint): T =
   let retcode = pcre.fullinfo(pattern.pcreObj, pattern.pcreExtra, opt, addr result)
@@ -308,7 +288,7 @@ proc matchesCrLf(pattern: Regex): bool =
   let newlineFlags = flags and (pcre.NEWLINE_CRLF or
                                 pcre.NEWLINE_ANY or
                                 pcre.NEWLINE_ANYCRLF)
-  if newLineFlags > 0u32:
+  if newlineFlags > 0u32:
     return true
 
   # get flags from build config
@@ -540,24 +520,33 @@ proc matchImpl(str: string, pattern: Regex, start, endpos: int, flags: int): Opt
 proc match*(str: string, pattern: Regex, start = 0, endpos = int.high): Option[RegexMatch] =
   ## Like `find(...)<#find,string,Regex,int>`_, but anchored to the start of the
   ## string.
-  ##
   runnableExamples:
-    doAssert "foo".match(re"f").isSome
-    doAssert "foo".match(re"o").isNone
+    assert "foo".match(re"f").isSome
+    assert "foo".match(re"o").isNone
 
+    assert "abc".match(re"(\w)").get.captures[0] == "a"
+    assert "abc".match(re"(?<letter>\w)").get.captures["letter"] == "a"
+    assert "abc".match(re"(\w)\w").get.captures[-1] == "ab"
+
+    assert "abc".match(re"(\w)").get.captureBounds[0] == 0 .. 0
+    assert 0 in "abc".match(re"(\w)").get.captureBounds
+    assert "abc".match(re"").get.captureBounds[-1] == 0 .. -1
+    assert "abc".match(re"abc").get.captureBounds[-1] == 0 .. 2
   return str.matchImpl(pattern, start, endpos, pcre.ANCHORED)
 
 iterator findIter*(str: string, pattern: Regex, start = 0, endpos = int.high): RegexMatch =
   ## Works the same as `find(...)<#find,string,Regex,int>`_, but finds every
-  ## non-overlapping match. `"2222".find(re"22")` is `"22", "22"`, not
-  ## `"22", "22", "22"`.
-  ##
+  ## non-overlapping match:
+  runnableExamples:
+    import std/sugar
+    assert collect(for a in "2222".findIter(re"22"): a.match) == @["22", "22"]
+     # not @["22", "22", "22"]
   ## Arguments are the same as `find(...)<#find,string,Regex,int>`_
   ##
   ## Variants:
   ##
   ## -  `proc findAll(...)` returns a `seq[string]`
-  # see pcredemo for explanation
+  # see pcredemo for explanation => https://www.pcre.org/original/doc/html/pcredemo.html
   let matchesCrLf = pattern.matchesCrLf()
   let unicode = uint32(getinfo[culong](pattern, pcre.INFO_OPTIONS) and
     pcre.UTF8) > 0u32
@@ -578,7 +567,7 @@ iterator findIter*(str: string, pattern: Regex, start = 0, endpos = int.high): R
       # either the end of the input or the string
       # cannot be split here - we also need to bail
       # if we've never matched and we've already tried to...
-      if offset >= strlen or neverMatched:
+      if flags == 0 or offset >= strlen or neverMatched: # All matches found
         break
 
       if matchesCrLf and offset < (str.len - 1) and
@@ -594,7 +583,6 @@ iterator findIter*(str: string, pattern: Regex, start = 0, endpos = int.high): R
     else:
       neverMatched = false
       offset = match.get.matchBounds.b + 1
-
       yield match.get
 
 proc find*(str: string, pattern: Regex, start = 0, endpos = int.high): Option[RegexMatch] =
@@ -602,11 +590,11 @@ proc find*(str: string, pattern: Regex, start = 0, endpos = int.high): Option[Re
   ## positions.
   ##
   ## `start`
-  ##     The start point at which to start matching. `|abc` is `0`;
+  ## :   The start point at which to start matching. `|abc` is `0`;
   ##     `a|bc` is `1`
   ##
   ## `endpos`
-  ##     The maximum index for a match; `int.high` means the end of the
+  ## :   The maximum index for a match; `int.high` means the end of the
   ##     string, otherwise it’s an inclusive upper bound.
   return str.matchImpl(pattern, start, endpos, 0)
 
@@ -619,11 +607,10 @@ proc contains*(str: string, pattern: Regex, start = 0, endpos = int.high): bool
   ## Determine if the string contains the given pattern between the end and
   ## start positions:
   ## This function is equivalent to `isSome(str.find(pattern, start, endpos))`.
-  ##
   runnableExamples:
-    doAssert "abc".contains(re"bc")
-    doAssert not "abc".contains(re"cd")
-    doAssert not "abc".contains(re"a", start = 1)
+    assert "abc".contains(re"bc")
+    assert not "abc".contains(re"cd")
+    assert not "abc".contains(re"a", start = 1)
 
   return isSome(str.find(pattern, start, endpos))
 
@@ -635,16 +622,16 @@ proc split*(str: string, pattern: Regex, maxSplit = -1, start = 0): seq[string]
   ##
   runnableExamples:
     # -  If the match is zero-width, then the string is still split:
-    doAssert "123".split(re"") == @["1", "2", "3"]
+    assert "123".split(re"") == @["1", "2", "3"]
 
     # -  If the pattern has a capture in it, it is added after the string
     #    split:
-    doAssert "12".split(re"(\d)") == @["", "1", "", "2", ""]
+    assert "12".split(re"(\d)") == @["", "1", "", "2", ""]
 
     # -  If `maxsplit != -1`, then the string will only be split
     #    `maxsplit - 1` times. This means that there will be `maxsplit`
     #    strings in the output seq.
-    doAssert "1.2.3".split(re"\.", maxsplit = 2) == @["1", "2.3"]
+    assert "1.2.3".split(re"\.", maxsplit = 2) == @["1", "2.3"]
 
   result = @[]
   var lastIdx = start
@@ -715,8 +702,7 @@ proc replace*(str: string, pattern: Regex,
   ## each match and the return value is the replacement value.
   ##
   ## If `subproc` is a `proc (string): string`, then it is executed with the
-  ## full text of the match and and the return value is the replacement
-  ## value.
+  ## full text of the match and the return value is the replacement value.
   ##
   ## If `subproc` is a string, the syntax is as follows:
   ##
@@ -747,9 +733,9 @@ proc escapeRe*(str: string): string {.gcsafe.} =
   ##
   ## Escaped char: `\ + * ? [ ^ ] $ ( ) { } = ! < > | : -`
   runnableExamples:
-    doAssert escapeRe("fly+wind") == "fly\\+wind"
-    doAssert escapeRe("!") == "\\!"
-    doAssert escapeRe("nim*") == "nim\\*"
+    assert escapeRe("fly+wind") == "fly\\+wind"
+    assert escapeRe("!") == "\\!"
+    assert escapeRe("nim*") == "nim\\*"
 
   #([\\+*?[^\]$(){}=!<>|:-])
   const SpecialCharMatcher = {'\\', '+', '*', '?', '[', '^', ']', '$', '(',
diff --git a/lib/impure/nre/private/util.nim b/lib/impure/nre/private/util.nim
index d227dcba3..ed8420776 100644
--- a/lib/impure/nre/private/util.nim
+++ b/lib/impure/nre/private/util.nim
@@ -1,5 +1,5 @@
 ## INTERNAL FILE FOR USE ONLY BY nre.nim.
-import tables
+import std/tables
 
 const Ident = {'a'..'z', 'A'..'Z', '0'..'9', '_', '\128'..'\255'}
 const StartIdent = Ident - {'0'..'9'}
diff --git a/lib/impure/rdstdin.nim b/lib/impure/rdstdin.nim
index c580b89d1..f4fc26380 100644
--- a/lib/impure/rdstdin.nim
+++ b/lib/impure/rdstdin.nim
@@ -22,11 +22,16 @@ runnableExamples("-r:off"):
     if line.len > 0: echo line
   echo "exiting"
 
+
 when defined(windows):
+  when defined(nimPreviewSlimSystem):
+    import std/syncio
+
   proc readLineFromStdin*(prompt: string): string {.
                           tags: [ReadIOEffect, WriteIOEffect].} =
     ## Reads a line from stdin.
     stdout.write(prompt)
+    stdout.flushFile()
     result = readLine(stdin)
 
   proc readLineFromStdin*(prompt: string, line: var string): bool {.
@@ -50,17 +55,7 @@ elif defined(genode):
     stdin.readLine(line)
 
 else:
-  import linenoise
-
-  proc readLineFromStdin*(prompt: string): string {.
-                          tags: [ReadIOEffect, WriteIOEffect].} =
-    var buffer = linenoise.readLine(prompt)
-    if isNil(buffer):
-      raise newException(IOError, "Linenoise returned nil")
-    result = $buffer
-    if result.len > 0:
-      historyAdd(buffer)
-    linenoise.free(buffer)
+  import std/linenoise
 
   proc readLineFromStdin*(prompt: string, line: var string): bool {.
                           tags: [ReadIOEffect, WriteIOEffect].} =
@@ -73,3 +68,7 @@ else:
       historyAdd(buffer)
     linenoise.free(buffer)
     result = true
+
+  proc readLineFromStdin*(prompt: string): string {.inline.} =
+    if not readLineFromStdin(prompt, result):
+      raise newException(IOError, "Linenoise returned nil")
diff --git a/lib/impure/re.nim b/lib/impure/re.nim
index 0c96876b9..053c6ab55 100644
--- a/lib/impure/re.nim
+++ b/lib/impure/re.nim
@@ -17,6 +17,10 @@ when defined(js):
 ## C library. This means that your application will depend on the PCRE
 ## library's licence when using this module, which should not be a problem
 ## though.
+##
+## .. note:: There are also alternative nimble packages such as [tinyre](https://github.com/khchen/tinyre)
+##   and [regex](https://github.com/nitely/nim-regex).
+##
 ## PCRE's licence follows:
 ##
 ## .. include:: ../../doc/regexprs.txt
@@ -32,7 +36,10 @@ runnableExamples:
     # can't match start of string since we're starting at 1
 
 import
-  pcre, strutils, rtarrays
+  std/[pcre, strutils, rtarrays]
+
+when defined(nimPreviewSlimSystem):
+  import std/syncio
 
 const
   MaxSubpatterns* = 20
@@ -41,12 +48,12 @@ const
 
 type
   RegexFlag* = enum     ## options for regular expressions
-    reIgnoreCase = 0,    ## do caseless matching
-    reMultiLine = 1,     ## `^` and `$` match newlines within data
-    reDotAll = 2,        ## `.` matches anything including NL
-    reExtended = 3,      ## ignore whitespace and `#` comments
-    reStudy = 4          ## study the expression (may be omitted if the
-                         ## expression will be used only once)
+    reIgnoreCase = 0,   ## do caseless matching
+    reMultiLine = 1,    ## `^` and `$` match newlines within data
+    reDotAll = 2,       ## `.` matches anything including NL
+    reExtended = 3,     ## ignore whitespace and `#` comments
+    reStudy = 4         ## study the expression (may be omitted if the
+                        ## expression will be used only once)
 
   RegexDesc = object
     h: ptr Pcre
@@ -58,10 +65,16 @@ type
     ## is raised if the pattern is no valid regular expression.
 
 when defined(gcDestructors):
-  proc `=destroy`(x: var RegexDesc) =
-    pcre.free_substring(cast[cstring](x.h))
-    if not isNil(x.e):
-      pcre.free_study(x.e)
+  when defined(nimAllowNonVarDestructor):
+    proc `=destroy`(x: RegexDesc) =
+      pcre.free_substring(cast[cstring](x.h))
+      if not isNil(x.e):
+        pcre.free_study(x.e)
+  else:
+    proc `=destroy`(x: var RegexDesc) =
+      pcre.free_substring(cast[cstring](x.h))
+      if not isNil(x.e):
+        pcre.free_study(x.e)
 
 proc raiseInvalidRegex(msg: string) {.noinline, noreturn.} =
   var e: ref RegexError
@@ -141,6 +154,10 @@ proc matchOrFind(buf: cstring, pattern: Regex, matches: var openArray[string],
     else: matches[i-1] = ""
   return rawMatches[1] - rawMatches[0]
 
+const MaxReBufSize* = high(cint)
+  ## Maximum PCRE (API 1) buffer start/size equal to `high(cint)`, which even
+  ## for 64-bit systems can be either 2`31`:sup:-1 or 2`63`:sup:-1.
+
 proc findBounds*(buf: cstring, pattern: Regex, matches: var openArray[string],
                  start = 0, bufSize: int): tuple[first, last: int] =
   ## returns the starting position and end position of `pattern` in `buf`
@@ -148,6 +165,9 @@ proc findBounds*(buf: cstring, pattern: Regex, matches: var openArray[string],
   ## and the captured
   ## substrings in the array `matches`. If it does not match, nothing
   ## is written into `matches` and `(-1,0)` is returned.
+  ##
+  ## Note: The memory for `matches` needs to be allocated before this function is
+  ## called, otherwise it will just remain empty.
   var
     rtarray = initRtArray[cint]((matches.len+1)*3)
     rawMatches = rtarray.getRawData
@@ -167,16 +187,27 @@ proc findBounds*(s: string, pattern: Regex, matches: var openArray[string],
   ## and the captured substrings in the array `matches`.
   ## If it does not match, nothing
   ## is written into `matches` and `(-1,0)` is returned.
-  result = findBounds(cstring(s), pattern, matches, start, s.len)
+  ##
+  ## .. note:: The memory for `matches` needs to be allocated before this function is called, otherwise it will just remain empty.
+  runnableExamples:
+    var matches = newSeq[string](1)
+    let (first, last) = findBounds("Hello World", re"(W\w+)", matches)
+    doAssert first == 6
+    doAssert last == 10
+    doAssert matches[0] == "World"
+  result = findBounds(cstring(s), pattern, matches,
+      min(start, MaxReBufSize), min(s.len, MaxReBufSize))
 
 proc findBounds*(buf: cstring, pattern: Regex,
                  matches: var openArray[tuple[first, last: int]],
-                 start = 0, bufSize = 0): tuple[first, last: int] =
+                 start = 0, bufSize: int): tuple[first, last: int] =
   ## returns the starting position and end position of `pattern` in `buf`
   ## (where `buf` has length `bufSize` and is not necessarily `'\0'` terminated),
   ## and the captured substrings in the array `matches`.
   ## If it does not match, nothing is written into `matches` and
   ## `(-1,0)` is returned.
+  ##
+  ## .. note:: The memory for `matches` needs to be allocated before this function is called, otherwise it will just remain empty.
   var
     rtarray = initRtArray[cint]((matches.len+1)*3)
     rawMatches = rtarray.getRawData
@@ -197,7 +228,28 @@ proc findBounds*(s: string, pattern: Regex,
   ## and the captured substrings in the array `matches`.
   ## If it does not match, nothing is written into `matches` and
   ## `(-1,0)` is returned.
-  result = findBounds(cstring(s), pattern, matches, start, s.len)
+  ##
+  ## .. note:: The memory for `matches` needs to be allocated before this function is called, otherwise it will just remain empty.
+  runnableExamples:
+    var matches = newSeq[tuple[first, last: int]](1)
+    let (first, last) = findBounds("Hello World", re"(\w+)", matches)
+    doAssert first == 0
+    doAssert last == 4
+    doAssert matches[0] == (0, 4)
+  result = findBounds(cstring(s), pattern, matches,
+      min(start, MaxReBufSize), min(s.len, MaxReBufSize))
+
+proc findBoundsImpl(buf: cstring, pattern: Regex,
+                    start = 0, bufSize = 0, flags = 0): tuple[first, last: int] =
+  var rtarray = initRtArray[cint](3)
+  let rawMatches = rtarray.getRawData
+  let res = pcre.exec(pattern.h, pattern.e, buf, bufSize.cint, start.cint, flags.int32,
+                cast[ptr cint](rawMatches), 3)
+
+  if res < 0'i32:
+    result = (-1, 0)
+  else:
+    result = (int(rawMatches[0]), int(rawMatches[1]-1))
 
 proc findBounds*(buf: cstring, pattern: Regex,
                  start = 0, bufSize: int): tuple[first, last: int] =
@@ -220,7 +272,8 @@ proc findBounds*(s: string, pattern: Regex,
   ## Note: there is a speed improvement if the matches do not need to be captured.
   runnableExamples:
     assert findBounds("01234abc89", re"abc") == (5,7)
-  result = findBounds(cstring(s), pattern, start, s.len)
+  result = findBounds(cstring(s), pattern,
+      min(start, MaxReBufSize), min(s.len, MaxReBufSize))
 
 proc matchOrFind(buf: cstring, pattern: Regex, start, bufSize: int, flags: cint): cint =
   var
@@ -236,6 +289,8 @@ proc matchLen*(s: string, pattern: Regex, matches: var openArray[string],
   ## the same as `match`, but it returns the length of the match,
   ## if there is no match, `-1` is returned. Note that a match length
   ## of zero can happen.
+  ##
+  ## .. note:: The memory for `matches` needs to be allocated before this function is called, otherwise it will just remain empty.
   result = matchOrFind(cstring(s), pattern, matches, start.cint, s.len.cint, pcre.ANCHORED)
 
 proc matchLen*(buf: cstring, pattern: Regex, matches: var openArray[string],
@@ -243,6 +298,8 @@ proc matchLen*(buf: cstring, pattern: Regex, matches: var openArray[string],
   ## the same as `match`, but it returns the length of the match,
   ## if there is no match, `-1` is returned. Note that a match length
   ## of zero can happen.
+  ##
+  ## .. note:: The memory for `matches` needs to be allocated before this function is called, otherwise it will just remain empty.
   return matchOrFind(buf, pattern, matches, start.cint, bufSize.cint, pcre.ANCHORED)
 
 proc matchLen*(s: string, pattern: Regex, start = 0): int {.inline.} =
@@ -273,6 +330,7 @@ proc match*(s: string, pattern: Regex, matches: var openArray[string],
   ## match, nothing is written into `matches` and `false` is
   ## returned.
   ##
+  ## .. note:: The memory for `matches` needs to be allocated before this function is called, otherwise it will just remain empty.
   runnableExamples:
     import std/sequtils
     var matches: array[2, string]
@@ -287,14 +345,18 @@ proc match*(buf: cstring, pattern: Regex, matches: var openArray[string],
   ## match, nothing is written into `matches` and `false` is
   ## returned.
   ## `buf` has length `bufSize` (not necessarily `'\0'` terminated).
+  ##
+  ## .. note:: The memory for `matches` needs to be allocated before this function is called, otherwise it will just remain empty.
   result = matchLen(buf, pattern, matches, start, bufSize) != -1
 
 proc find*(buf: cstring, pattern: Regex, matches: var openArray[string],
-           start = 0, bufSize = 0): int =
+           start = 0, bufSize: int): int =
   ## returns the starting position of `pattern` in `buf` and the captured
   ## substrings in the array `matches`. If it does not match, nothing
   ## is written into `matches` and `-1` is returned.
   ## `buf` has length `bufSize` (not necessarily `'\0'` terminated).
+  ##
+  ## .. note:: The memory for `matches` needs to be allocated before this function is called, otherwise it will just remain empty.
   var
     rtarray = initRtArray[cint]((matches.len+1)*3)
     rawMatches = rtarray.getRawData
@@ -313,6 +375,8 @@ proc find*(s: string, pattern: Regex, matches: var openArray[string],
   ## returns the starting position of `pattern` in `s` and the captured
   ## substrings in the array `matches`. If it does not match, nothing
   ## is written into `matches` and `-1` is returned.
+  ##
+  ## .. note:: The memory for `matches` needs to be allocated before this function is called, otherwise it will just remain empty.
   result = find(cstring(s), pattern, matches, start, s.len)
 
 proc find*(buf: cstring, pattern: Regex, start = 0, bufSize: int): int =
@@ -382,7 +446,7 @@ iterator findAll*(buf: cstring, pattern: Regex, start = 0, bufSize: int): string
 
 proc findAll*(s: string, pattern: Regex, start = 0): seq[string] {.inline.} =
   ## returns all matching `substrings` of `s` that match `pattern`.
-  ## If it does not match, @[] is returned.
+  ## If it does not match, `@[]` is returned.
   result = @[]
   for x in findAll(s, pattern, start): result.add x
 
@@ -396,7 +460,7 @@ template `=~` *(s: string, pattern: Regex): untyped =
       elif line =~ re"\s*(\#.*)": # matches a comment
         # note that the implicit `matches` array is different from 1st branch
         result = $(matches[0],)
-      else: doAssert false
+      else: raiseAssert "unreachable"
       doAssert not declared(matches)
     doAssert parse("NAME = LENA") == """("NAME", "LENA")"""
     doAssert parse("   # comment ... ") == """("# comment ... ",)"""
@@ -414,6 +478,8 @@ proc contains*(s: string, pattern: Regex, start = 0): bool {.inline.} =
 proc contains*(s: string, pattern: Regex, matches: var openArray[string],
               start = 0): bool {.inline.} =
   ## same as `find(s, pattern, matches, start) >= 0`
+  ##
+  ## .. note:: The memory for `matches` needs to be allocated before this function is called, otherwise it will just remain empty.
   return find(s, pattern, matches, start) >= 0
 
 proc startsWith*(s: string, prefix: Regex): bool {.inline.} =
@@ -433,12 +499,16 @@ proc replace*(s: string, sub: Regex, by = ""): string =
     doAssert "var1=key; var2=key2".replace(re"(\w+)=(\w+)", "?") == "?; ?"
   result = ""
   var prev = 0
+  var flags = int32(0)
   while prev < s.len:
-    var match = findBounds(s, sub, prev)
+    var match = findBoundsImpl(s.cstring, sub, prev, s.len, flags)
+    flags = 0
     if match.first < 0: break
     add(result, substr(s, prev, match.first-1))
     add(result, by)
-    if match.last + 1 == prev: break
+    if match.first > match.last:
+      # 0-len match
+      flags = pcre.NOTEMPTY_ATSTART
     prev = match.last + 1
   add(result, substr(s, prev))
 
@@ -499,19 +569,22 @@ iterator split*(s: string, sep: Regex; maxsplit = -1): string =
       @["", "this", "is", "an", "example", ""]
   var last = 0
   var splits = maxsplit
-  var x: int
+  var x = -1
+  if len(s) == 0:
+    last = 1
+  if matchLen(s, sep, 0) == 0:
+    x = 0
   while last <= len(s):
     var first = last
     var sepLen = 1
+    if x == 0:
+      inc(last)
     while last < len(s):
       x = matchLen(s, sep, last)
       if x >= 0:
         sepLen = x
         break
       inc(last)
-    if x == 0:
-      if last >= len(s): break
-      inc last
     if splits == 0: last = len(s)
     yield substr(s, first, last-1)
     if splits == 0: break