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-rw-r--r--lib/pure/parsecfg.nim426
1 files changed, 254 insertions, 172 deletions
diff --git a/lib/pure/parsecfg.nim b/lib/pure/parsecfg.nim
index 5fa2d8dc3..8a43daf54 100644
--- a/lib/pure/parsecfg.nim
+++ b/lib/pure/parsecfg.nim
@@ -7,119 +7,209 @@
 #    distribution, for details about the copyright.
 #
 
-## The ``parsecfg`` module implements a high performance configuration file
-## parser. The configuration file's syntax is similar to the Windows ``.ini``
+## The `parsecfg` module implements a high performance configuration file
+## parser. The configuration file's syntax is similar to the Windows `.ini`
 ## format, but much more powerful, as it is not a line based parser. String
 ## literals, raw string literals and triple quoted string literals are supported
 ## as in the Nim programming language.
-
-## This is an example of how a configuration file may look like:
+##
+## Example of how a configuration file may look like:
 ##
 ## .. include:: ../../doc/mytest.cfg
 ##     :literal:
-## The file ``examples/parsecfgex.nim`` demonstrates how to use the
-## configuration file parser:
-##
-## .. code-block:: nim
-##     :file: ../../examples/parsecfgex.nim
-##
-## Examples
-## --------
-##
-## This is an example of a configuration file.
-##
-## ::
 ##
+## Here is an example of how to use the configuration file parser:
+runnableExamples("-r:off"):
+  import std/[strutils, streams]
+
+  let configFile = "example.ini"
+  var f = newFileStream(configFile, fmRead)
+  assert f != nil, "cannot open " & configFile
+  var p: CfgParser
+  open(p, f, configFile)
+  while true:
+    var e = next(p)
+    case e.kind
+    of cfgEof: break
+    of cfgSectionStart:   ## a `[section]` has been parsed
+      echo "new section: " & e.section
+    of cfgKeyValuePair:
+      echo "key-value-pair: " & e.key & ": " & e.value
+    of cfgOption:
+      echo "command: " & e.key & ": " & e.value
+    of cfgError:
+      echo e.msg
+  close(p)
+
+##[
+## Configuration file example
+]##
+
+##     ```none
 ##     charset = "utf-8"
 ##     [Package]
 ##     name = "hello"
 ##     --threads:on
 ##     [Author]
-##     name = "lihf8515"
-##     qq = "10214028"
-##     email = "lihaifeng@wxm.com"
-##
-## Creating a configuration file.
-## ==============================
-## .. code-block:: nim
-##
-##     import parsecfg
-##     var dict=newConfig()
-##     dict.setSectionKey("","charset","utf-8")
-##     dict.setSectionKey("Package","name","hello")
-##     dict.setSectionKey("Package","--threads","on")
-##     dict.setSectionKey("Author","name","lihf8515")
-##     dict.setSectionKey("Author","qq","10214028")
-##     dict.setSectionKey("Author","email","lihaifeng@wxm.com")
-##     dict.writeConfig("config.ini")
-##
-## Reading a configuration file.
-## =============================
-## .. code-block:: nim
-##
-##     import parsecfg
-##     var dict = loadConfig("config.ini")
-##     var charset = dict.getSectionValue("","charset")
-##     var threads = dict.getSectionValue("Package","--threads")
-##     var pname = dict.getSectionValue("Package","name")
-##     var name = dict.getSectionValue("Author","name")
-##     var qq = dict.getSectionValue("Author","qq")
-##     var email = dict.getSectionValue("Author","email")
-##     echo pname & "\n" & name & "\n" & qq & "\n" & email
-##
-## Modifying a configuration file.
-## ===============================
-## .. code-block:: nim
-##
-##     import parsecfg
-##     var dict = loadConfig("config.ini")
-##     dict.setSectionKey("Author","name","lhf")
-##     dict.writeConfig("config.ini")
-##
-## Deleting a section key in a configuration file.
-## ===============================================
-## .. code-block:: nim
-##
-##     import parsecfg
-##     var dict = loadConfig("config.ini")
-##     dict.delSectionKey("Author","email")
-##     dict.writeConfig("config.ini")
-
-import
-  hashes, strutils, lexbase, streams, tables
+##     name = "nim-lang"
+##     website = "nim-lang.org"
+##     ```
+
+##[
+## Creating a configuration file
+]##
+
+runnableExamples:
+  var dict = newConfig()
+  dict.setSectionKey("","charset", "utf-8")
+  dict.setSectionKey("Package", "name", "hello")
+  dict.setSectionKey("Package", "--threads", "on")
+  dict.setSectionKey("Author", "name", "nim-lang")
+  dict.setSectionKey("Author", "website", "nim-lang.org")
+  assert $dict == """
+charset=utf-8
+[Package]
+name=hello
+--threads:on
+[Author]
+name=nim-lang
+website=nim-lang.org
+"""
+
+##[
+## Reading a configuration file
+]##
+
+runnableExamples("-r:off"):
+  let dict = loadConfig("config.ini")
+  let charset = dict.getSectionValue("","charset")
+  let threads = dict.getSectionValue("Package","--threads")
+  let pname = dict.getSectionValue("Package","name")
+  let name = dict.getSectionValue("Author","name")
+  let website = dict.getSectionValue("Author","website")
+  echo pname & "\n" & name & "\n" & website
+
+##[
+## Modifying a configuration file
+]##
+
+runnableExamples("-r:off"):
+  var dict = loadConfig("config.ini")
+  dict.setSectionKey("Author", "name", "nim-lang")
+  dict.writeConfig("config.ini")
+
+##[
+## Deleting a section key in a configuration file
+]##
+
+runnableExamples("-r:off"):
+  var dict = loadConfig("config.ini")
+  dict.delSectionKey("Author", "website")
+  dict.writeConfig("config.ini")
+
+##[
+## Supported INI File structure
+]##
+
+# taken from https://docs.python.org/3/library/configparser.html#supported-ini-file-structure
+runnableExamples:
+  import std/streams
+
+  var dict = loadConfig(newStringStream("""[Simple Values]
+    key=value
+    spaces in keys=allowed
+    spaces in values=allowed as well
+    spaces around the delimiter = obviously
+    you can also use : to delimit keys from values
+    [All Values Are Strings]
+    values like this: 19990429
+    or this: 3.14159265359
+    are they treated as numbers : no
+    integers floats and booleans are held as: strings
+    can use the API to get converted values directly: true
+    [No Values]
+    key_without_value
+    # empty string value is not allowed =
+    [ Seletion A   ]
+    space around section name will be ignored
+    [You can use comments]
+    # like this
+    ; or this
+    # By default only in an empty line.
+    # Inline comments can be harmful because they prevent users
+    # from using the delimiting characters as parts of values.
+    # That being said, this can be customized.
+        [Sections Can Be Indented]
+            can_values_be_as_well = True
+            does_that_mean_anything_special = False
+            purpose = formatting for readability
+            # Did I mention we can indent comments, too?
+    """)
+  )
+
+  let section1 = "Simple Values"
+  assert dict.getSectionValue(section1, "key") == "value"
+  assert dict.getSectionValue(section1, "spaces in keys") == "allowed"
+  assert dict.getSectionValue(section1, "spaces in values") == "allowed as well"
+  assert dict.getSectionValue(section1, "spaces around the delimiter") == "obviously"
+  assert dict.getSectionValue(section1, "you can also use") == "to delimit keys from values"
+
+  let section2 = "All Values Are Strings"
+  assert dict.getSectionValue(section2, "values like this") == "19990429"
+  assert dict.getSectionValue(section2, "or this") == "3.14159265359"
+  assert dict.getSectionValue(section2, "are they treated as numbers") == "no"
+  assert dict.getSectionValue(section2, "integers floats and booleans are held as") == "strings"
+  assert dict.getSectionValue(section2, "can use the API to get converted values directly") == "true"
+
+  let section3 = "Seletion A"
+  assert dict.getSectionValue(section3, 
+    "space around section name will be ignored", "not an empty value") == ""
+
+  let section4 = "Sections Can Be Indented"
+  assert dict.getSectionValue(section4, "can_values_be_as_well") == "True"
+  assert dict.getSectionValue(section4, "does_that_mean_anything_special") == "False"
+  assert dict.getSectionValue(section4, "purpose") == "formatting for readability"
+
+import std/[strutils, lexbase, streams, tables]
+import std/private/decode_helpers
+import std/private/since
+
+when defined(nimPreviewSlimSystem):
+  import std/syncio
 
 include "system/inclrtl"
 
+
 type
   CfgEventKind* = enum ## enumeration of all events that may occur when parsing
-    cfgEof,             ## end of file reached
-    cfgSectionStart,    ## a ``[section]`` has been parsed
-    cfgKeyValuePair,    ## a ``key=value`` pair has been detected
-    cfgOption,          ## a ``--key=value`` command line option
-    cfgError            ## an error occurred during parsing
+    cfgEof,            ## end of file reached
+    cfgSectionStart,   ## a `[section]` has been parsed
+    cfgKeyValuePair,   ## a `key=value` pair has been detected
+    cfgOption,         ## a `--key=value` command line option
+    cfgError           ## an error occurred during parsing
 
   CfgEvent* = object of RootObj ## describes a parsing event
     case kind*: CfgEventKind    ## the kind of the event
     of cfgEof: nil
     of cfgSectionStart:
-      section*: string           ## `section` contains the name of the
-                                 ## parsed section start (syntax: ``[section]``)
+      section*: string          ## `section` contains the name of the
+                                ## parsed section start (syntax: `[section]`)
     of cfgKeyValuePair, cfgOption:
-      key*, value*: string       ## contains the (key, value) pair if an option
-                                 ## of the form ``--key: value`` or an ordinary
-                                 ## ``key= value`` pair has been parsed.
-                                 ## ``value==""`` if it was not specified in the
-                                 ## configuration file.
-    of cfgError:                 ## the parser encountered an error: `msg`
-      msg*: string               ## contains the error message. No exceptions
-                                 ## are thrown if a parse error occurs.
+      key*, value*: string      ## contains the (key, value) pair if an option
+                                ## of the form `--key: value` or an ordinary
+                                ## `key= value` pair has been parsed.
+                                ## `value==""` if it was not specified in the
+                                ## configuration file.
+    of cfgError:                ## the parser encountered an error: `msg`
+      msg*: string              ## contains the error message. No exceptions
+                                ## are thrown if a parse error occurs.
 
   TokKind = enum
     tkInvalid, tkEof,
     tkSymbol, tkEquals, tkColon, tkBracketLe, tkBracketRi, tkDashDash
-  Token = object             # a token
-    kind: TokKind            # the type of the token
-    literal: string          # the parsed (string) literal
+  Token = object    # a token
+    kind: TokKind   # the type of the token
+    literal: string # the parsed (string) literal
 
   CfgParser* = object of BaseLexer ## the parser object.
     tok: Token
@@ -128,13 +218,13 @@ type
 # implementation
 
 const
-  SymChars = {'a'..'z', 'A'..'Z', '0'..'9', '_', '\x80'..'\xFF', '.', '/', '\\', '-'}
+  SymChars = {'a'..'z', 'A'..'Z', '0'..'9', '_', ' ', '\x80'..'\xFF', '.', '/', '\\', '-'}
 
 proc rawGetTok(c: var CfgParser, tok: var Token) {.gcsafe.}
 
 proc open*(c: var CfgParser, input: Stream, filename: string,
            lineOffset = 0) {.rtl, extern: "npc$1".} =
-  ## initializes the parser with an input stream. `Filename` is only used
+  ## Initializes the parser with an input stream. `Filename` is only used
   ## for nice error messages. `lineOffset` can be used to influence the line
   ## number information in the generated error messages.
   lexbase.open(c, input)
@@ -145,42 +235,28 @@ proc open*(c: var CfgParser, input: Stream, filename: string,
   rawGetTok(c, c.tok)
 
 proc close*(c: var CfgParser) {.rtl, extern: "npc$1".} =
-  ## closes the parser `c` and its associated input stream.
+  ## Closes the parser `c` and its associated input stream.
   lexbase.close(c)
 
 proc getColumn*(c: CfgParser): int {.rtl, extern: "npc$1".} =
-  ## get the current column the parser has arrived at.
+  ## Gets the current column the parser has arrived at.
   result = getColNumber(c, c.bufpos)
 
 proc getLine*(c: CfgParser): int {.rtl, extern: "npc$1".} =
-  ## get the current line the parser has arrived at.
+  ## Gets the current line the parser has arrived at.
   result = c.lineNumber
 
 proc getFilename*(c: CfgParser): string {.rtl, extern: "npc$1".} =
-  ## get the filename of the file that the parser processes.
+  ## Gets the filename of the file that the parser processes.
   result = c.filename
 
-proc handleHexChar(c: var CfgParser, xi: var int) =
-  case c.buf[c.bufpos]
-  of '0'..'9':
-    xi = (xi shl 4) or (ord(c.buf[c.bufpos]) - ord('0'))
-    inc(c.bufpos)
-  of 'a'..'f':
-    xi = (xi shl 4) or (ord(c.buf[c.bufpos]) - ord('a') + 10)
-    inc(c.bufpos)
-  of 'A'..'F':
-    xi = (xi shl 4) or (ord(c.buf[c.bufpos]) - ord('A') + 10)
-    inc(c.bufpos)
-  else:
-    discard
-
 proc handleDecChars(c: var CfgParser, xi: var int) =
   while c.buf[c.bufpos] in {'0'..'9'}:
     xi = (xi * 10) + (ord(c.buf[c.bufpos]) - ord('0'))
     inc(c.bufpos)
 
 proc getEscapedChar(c: var CfgParser, tok: var Token) =
-  inc(c.bufpos)               # skip '\'
+  inc(c.bufpos) # skip '\'
   case c.buf[c.bufpos]
   of 'n', 'N':
     add(tok.literal, "\n")
@@ -218,8 +294,10 @@ proc getEscapedChar(c: var CfgParser, tok: var Token) =
   of 'x', 'X':
     inc(c.bufpos)
     var xi = 0
-    handleHexChar(c, xi)
-    handleHexChar(c, xi)
+    if handleHexChar(c.buf[c.bufpos], xi):
+      inc(c.bufpos)
+      if handleHexChar(c.buf[c.bufpos], xi):
+        inc(c.bufpos)
     add(tok.literal, chr(xi))
   of '0'..'9':
     var xi = 0
@@ -235,38 +313,35 @@ proc handleCRLF(c: var CfgParser, pos: int): int =
   else: result = pos
 
 proc getString(c: var CfgParser, tok: var Token, rawMode: bool) =
-  var pos = c.bufpos + 1          # skip "
-  var buf = c.buf                 # put `buf` in a register
+  var pos = c.bufpos + 1 # skip "
   tok.kind = tkSymbol
-  if (buf[pos] == '"') and (buf[pos + 1] == '"'):
+  if (c.buf[pos] == '"') and (c.buf[pos + 1] == '"'):
     # long string literal:
-    inc(pos, 2)               # skip ""
+    inc(pos, 2) # skip ""
                               # skip leading newline:
     pos = handleCRLF(c, pos)
-    buf = c.buf
     while true:
-      case buf[pos]
+      case c.buf[pos]
       of '"':
-        if (buf[pos + 1] == '"') and (buf[pos + 2] == '"'): break
+        if (c.buf[pos + 1] == '"') and (c.buf[pos + 2] == '"'): break
         add(tok.literal, '"')
         inc(pos)
       of '\c', '\L':
         pos = handleCRLF(c, pos)
-        buf = c.buf
         add(tok.literal, "\n")
       of lexbase.EndOfFile:
         tok.kind = tkInvalid
         break
       else:
-        add(tok.literal, buf[pos])
+        add(tok.literal, c.buf[pos])
         inc(pos)
-    c.bufpos = pos + 3       # skip the three """
+    c.bufpos = pos + 3 # skip the three """
   else:
     # ordinary string literal
     while true:
-      var ch = buf[pos]
+      var ch = c.buf[pos]
       if ch == '"':
-        inc(pos)              # skip '"'
+        inc(pos) # skip '"'
         break
       if ch in {'\c', '\L', lexbase.EndOfFile}:
         tok.kind = tkInvalid
@@ -282,28 +357,29 @@ proc getString(c: var CfgParser, tok: var Token, rawMode: bool) =
 
 proc getSymbol(c: var CfgParser, tok: var Token) =
   var pos = c.bufpos
-  var buf = c.buf
   while true:
-    add(tok.literal, buf[pos])
+    add(tok.literal, c.buf[pos])
     inc(pos)
-    if not (buf[pos] in SymChars): break
+    if not (c.buf[pos] in SymChars): break
+
+  while tok.literal.len > 0 and tok.literal[^1] == ' ':
+    tok.literal.setLen(tok.literal.len - 1)
+
   c.bufpos = pos
   tok.kind = tkSymbol
 
 proc skip(c: var CfgParser) =
   var pos = c.bufpos
-  var buf = c.buf
   while true:
-    case buf[pos]
+    case c.buf[pos]
     of ' ', '\t':
       inc(pos)
     of '#', ';':
-      while not (buf[pos] in {'\c', '\L', lexbase.EndOfFile}): inc(pos)
+      while not (c.buf[pos] in {'\c', '\L', lexbase.EndOfFile}): inc(pos)
     of '\c', '\L':
       pos = handleCRLF(c, pos)
-      buf = c.buf
     else:
-      break                   # EndOfFile also leaves the loop
+      break # EndOfFile also leaves the loop
   c.bufpos = pos
 
 proc rawGetTok(c: var CfgParser, tok: var Token) =
@@ -337,7 +413,7 @@ proc rawGetTok(c: var CfgParser, tok: var Token) =
   of '[':
     tok.kind = tkBracketLe
     inc(c.bufpos)
-    tok.literal = "]"
+    tok.literal = "["
   of ']':
     tok.kind = tkBracketRi
     inc(c.bufpos)
@@ -350,19 +426,19 @@ proc rawGetTok(c: var CfgParser, tok: var Token) =
   else: getSymbol(c, tok)
 
 proc errorStr*(c: CfgParser, msg: string): string {.rtl, extern: "npc$1".} =
-  ## returns a properly formatted error message containing current line and
+  ## Returns a properly formatted error message containing current line and
   ## column information.
   result = `%`("$1($2, $3) Error: $4",
-               [c.filename, $getLine(c), $getColumn(c), msg])
+                [c.filename, $getLine(c), $getColumn(c), msg])
 
 proc warningStr*(c: CfgParser, msg: string): string {.rtl, extern: "npc$1".} =
-  ## returns a properly formatted warning message containing current line and
+  ## Returns a properly formatted warning message containing current line and
   ## column information.
   result = `%`("$1($2, $3) Warning: $4",
-               [c.filename, $getLine(c), $getColumn(c), msg])
+                [c.filename, $getLine(c), $getColumn(c), msg])
 
 proc ignoreMsg*(c: CfgParser, e: CfgEvent): string {.rtl, extern: "npc$1".} =
-  ## returns a properly formatted warning message containing that
+  ## Returns a properly formatted warning message containing that
   ## an entry is ignored.
   case e.kind
   of cfgSectionStart: result = c.warningStr("section ignored: " & e.section)
@@ -374,29 +450,29 @@ proc ignoreMsg*(c: CfgParser, e: CfgEvent): string {.rtl, extern: "npc$1".} =
 
 proc getKeyValPair(c: var CfgParser, kind: CfgEventKind): CfgEvent =
   if c.tok.kind == tkSymbol:
-    result.kind = kind
-    result.key = c.tok.literal
-    result.value = ""
+    case kind
+    of cfgOption, cfgKeyValuePair:
+      result = CfgEvent(kind: kind, key: c.tok.literal.move, value: "")
+    else: discard
     rawGetTok(c, c.tok)
     if c.tok.kind in {tkEquals, tkColon}:
       rawGetTok(c, c.tok)
       if c.tok.kind == tkSymbol:
         result.value = c.tok.literal
       else:
-        reset result
-        result.kind = cfgError
-        result.msg = errorStr(c, "symbol expected, but found: " & c.tok.literal)
+        result = CfgEvent(kind: cfgError,
+          msg: errorStr(c, "symbol expected, but found: " & c.tok.literal))
       rawGetTok(c, c.tok)
   else:
-    result.kind = cfgError
-    result.msg = errorStr(c, "symbol expected, but found: " & c.tok.literal)
+    result = CfgEvent(kind: cfgError,
+      msg: errorStr(c, "symbol expected, but found: " & c.tok.literal))
     rawGetTok(c, c.tok)
 
 proc next*(c: var CfgParser): CfgEvent {.rtl, extern: "npc$1".} =
-  ## retrieves the first/next event. This controls the parser.
+  ## Retrieves the first/next event. This controls the parser.
   case c.tok.kind
   of tkEof:
-    result.kind = cfgEof
+    result = CfgEvent(kind: cfgEof)
   of tkDashDash:
     rawGetTok(c, c.tok)
     result = getKeyValPair(c, cfgOption)
@@ -405,21 +481,19 @@ proc next*(c: var CfgParser): CfgEvent {.rtl, extern: "npc$1".} =
   of tkBracketLe:
     rawGetTok(c, c.tok)
     if c.tok.kind == tkSymbol:
-      result.kind = cfgSectionStart
-      result.section = c.tok.literal
+      result = CfgEvent(kind: cfgSectionStart, section: c.tok.literal.move)
     else:
-      result.kind = cfgError
-      result.msg = errorStr(c, "symbol expected, but found: " & c.tok.literal)
+      result = CfgEvent(kind: cfgError,
+        msg: errorStr(c, "symbol expected, but found: " & c.tok.literal))
     rawGetTok(c, c.tok)
     if c.tok.kind == tkBracketRi:
       rawGetTok(c, c.tok)
     else:
-      reset(result)
-      result.kind = cfgError
-      result.msg = errorStr(c, "']' expected, but found: " & c.tok.literal)
+      result = CfgEvent(kind: cfgError,
+        msg: errorStr(c, "']' expected, but found: " & c.tok.literal))
   of tkInvalid, tkEquals, tkColon, tkBracketRi:
-    result.kind = cfgError
-    result.msg = errorStr(c, "invalid token: " & c.tok.literal)
+    result = CfgEvent(kind: cfgError,
+      msg: errorStr(c, "invalid token: " & c.tok.literal))
     rawGetTok(c, c.tok)
 
 # ---------------- Configuration file related operations ----------------
@@ -427,12 +501,12 @@ type
   Config* = OrderedTableRef[string, OrderedTableRef[string, string]]
 
 proc newConfig*(): Config =
-  ## Create a new configuration table.
+  ## Creates a new configuration table.
   ## Useful when wanting to create a configuration file.
   result = newOrderedTable[string, OrderedTableRef[string, string]]()
 
 proc loadConfig*(stream: Stream, filename: string = "[stream]"): Config =
-  ## Load the specified configuration from stream into a new Config instance.
+  ## Loads the specified configuration from stream into a new Config instance.
   ## `filename` parameter is only used for nicer error messages.
   var dict = newOrderedTable[string, OrderedTableRef[string, string]]()
   var curSection = "" ## Current section,
@@ -465,7 +539,7 @@ proc loadConfig*(stream: Stream, filename: string = "[stream]"): Config =
   result = dict
 
 proc loadConfig*(filename: string): Config =
-  ## Load the specified configuration file into a new Config instance.
+  ## Loads the specified configuration file into a new Config instance.
   let file = open(filename, fmRead)
   let fileStream = newFileStream(file)
   defer: fileStream.close()
@@ -477,12 +551,12 @@ proc replace(s: string): string =
   while i < s.len():
     if s[i] == '\\':
       d.add(r"\\")
-    elif s[i] == '\c' and s[i+1] == '\L':
-      d.add(r"\n")
+    elif s[i] == '\c' and s[i+1] == '\l':
+      d.add(r"\c\l")
       inc(i)
     elif s[i] == '\c':
       d.add(r"\n")
-    elif s[i] == '\L':
+    elif s[i] == '\l':
       d.add(r"\n")
     else:
       d.add(s[i])
@@ -490,9 +564,9 @@ proc replace(s: string): string =
   result = d
 
 proc writeConfig*(dict: Config, stream: Stream) =
-  ## Writes the contents of the table to the specified stream
+  ## Writes the contents of the table to the specified stream.
   ##
-  ## **Note:** Comment statement will be ignored.
+  ## .. note:: Comment statement will be ignored.
   for section, sectionData in dict.pairs():
     if section != "": ## Not general section
       if not allCharsInSet(section, SymChars): ## Non system character
@@ -531,7 +605,8 @@ proc writeConfig*(dict: Config, stream: Stream) =
 
 proc `$`*(dict: Config): string =
   ## Writes the contents of the table to string.
-  ## Note: Comment statement will be ignored.
+  ## 
+  ## .. note:: Comment statement will be ignored.
   let stream = newStringStream()
   defer: stream.close()
   dict.writeConfig(stream)
@@ -539,21 +614,23 @@ proc `$`*(dict: Config): string =
 
 proc writeConfig*(dict: Config, filename: string) =
   ## Writes the contents of the table to the specified configuration file.
-  ## Note: Comment statement will be ignored.
+  ## 
+  ## .. note:: Comment statement will be ignored.
   let file = open(filename, fmWrite)
   defer: file.close()
   let fileStream = newFileStream(file)
   dict.writeConfig(fileStream)
 
-proc getSectionValue*(dict: Config, section, key: string): string =
-  ## Gets the Key value of the specified Section.
-  if dict.haskey(section):
+proc getSectionValue*(dict: Config, section, key: string, defaultVal = ""): string =
+  ## Gets the key value of the specified Section.
+  ## Returns the specified default value if the specified key does not exist.
+  if dict.hasKey(section):
     if dict[section].hasKey(key):
       result = dict[section][key]
     else:
-      result = ""
+      result = defaultVal
   else:
-    result = ""
+    result = defaultVal
 
 proc setSectionKey*(dict: var Config, section, key, value: string) =
   ## Sets the Key value of the specified Section.
@@ -568,10 +645,15 @@ proc delSection*(dict: var Config, section: string) =
   dict.del(section)
 
 proc delSectionKey*(dict: var Config, section, key: string) =
-  ## Delete the key of the specified section.
-  if dict.haskey(section):
+  ## Deletes the key of the specified section.
+  if dict.hasKey(section):
     if dict[section].hasKey(key):
-      if dict[section].len() == 1:
+      if dict[section].len == 1:
         dict.del(section)
       else:
         dict[section].del(key)
+
+iterator sections*(dict: Config): lent string {.since: (1, 5).} =
+  ## Iterates through the sections in the `dict`.
+  for section in dict.keys:
+    yield section