# # # Nim's Runtime Library # (c) Copyright 2015 Andreas Rumpf # # See the file "copying.txt", included in this # distribution, for details about the copyright. # include "system/inclrtl" ## This module contains the interface to the compiler's abstract syntax ## tree (`AST`:idx:). Macros operate on this tree. ## ## See also: ## * `macros tutorial `_ ## * `macros section in Nim manual `_ ## .. include:: ../../doc/astspec.txt # If you look for the implementation of the magic symbol # ``{.magic: "Foo".}``, search for `mFoo` and `opcFoo`. type NimNodeKind* = enum nnkNone, nnkEmpty, nnkIdent, nnkSym, nnkType, nnkCharLit, nnkIntLit, nnkInt8Lit, nnkInt16Lit, nnkInt32Lit, nnkInt64Lit, nnkUIntLit, nnkUInt8Lit, nnkUInt16Lit, nnkUInt32Lit, nnkUInt64Lit, nnkFloatLit, nnkFloat32Lit, nnkFloat64Lit, nnkFloat128Lit, nnkStrLit, nnkRStrLit, nnkTripleStrLit, nnkNilLit, nnkComesFrom, nnkDotCall, nnkCommand, nnkCall, nnkCallStrLit, nnkInfix, nnkPrefix, nnkPostfix, nnkHiddenCallConv, nnkExprEqExpr, nnkExprColonExpr, nnkIdentDefs, nnkVarTuple, nnkPar, nnkObjConstr, nnkCurly, nnkCurlyExpr, nnkBracket, nnkBracketExpr, nnkPragmaExpr, nnkRange, nnkDotExpr, nnkCheckedFieldExpr, nnkDerefExpr, nnkIfExpr, nnkElifExpr, nnkElseExpr, nnkLambda, nnkDo, nnkAccQuoted, nnkTableConstr, nnkBind, nnkClosedSymChoice, nnkOpenSymChoice, nnkHiddenStdConv, nnkHiddenSubConv, nnkConv, nnkCast, nnkStaticExpr, nnkAddr, nnkHiddenAddr, nnkHiddenDeref, nnkObjDownConv, nnkObjUpConv, nnkChckRangeF, nnkChckRange64, nnkChckRange, nnkStringToCString, nnkCStringToString, nnkAsgn, nnkFastAsgn, nnkGenericParams, nnkFormalParams, nnkOfInherit, nnkImportAs, nnkProcDef, nnkMethodDef, nnkConverterDef, nnkMacroDef, nnkTemplateDef, nnkIteratorDef, nnkOfBranch, nnkElifBranch, nnkExceptBranch, nnkElse, nnkAsmStmt, nnkPragma, nnkPragmaBlock, nnkIfStmt, nnkWhenStmt, nnkForStmt, nnkParForStmt, nnkWhileStmt, nnkCaseStmt, nnkTypeSection, nnkVarSection, nnkLetSection, nnkConstSection, nnkConstDef, nnkTypeDef, nnkYieldStmt, nnkDefer, nnkTryStmt, nnkFinally, nnkRaiseStmt, nnkReturnStmt, nnkBreakStmt, nnkContinueStmt, nnkBlockStmt, nnkStaticStmt, nnkDiscardStmt, nnkStmtList, nnkImportStmt, nnkImportExceptStmt, nnkExportStmt, nnkExportExceptStmt, nnkFromStmt, nnkIncludeStmt, nnkBindStmt, nnkMixinStmt, nnkUsingStmt, nnkCommentStmt, nnkStmtListExpr, nnkBlockExpr, nnkStmtListType, nnkBlockType, nnkWith, nnkWithout, nnkTypeOfExpr, nnkObjectTy, nnkTupleTy, nnkTupleClassTy, nnkTypeClassTy, nnkStaticTy, nnkRecList, nnkRecCase, nnkRecWhen, nnkRefTy, nnkPtrTy, nnkVarTy, nnkConstTy, nnkMutableTy, nnkDistinctTy, nnkProcTy, nnkIteratorTy, # iterator type nnkSharedTy, # 'shared T' nnkEnumTy, nnkEnumFieldDef, nnkArglist, nnkPattern nnkHiddenTryStmt, nnkClosure, nnkGotoState, nnkState, nnkBreakState, nnkFuncDef, nnkTupleConstr NimNodeKinds* = set[NimNodeKind] NimTypeKind* = enum # some types are no longer used, see ast.nim ntyNone, ntyBool, ntyChar, ntyEmpty, ntyAlias, ntyNil, ntyExpr, ntyStmt, ntyTypeDesc, ntyGenericInvocation, ntyGenericBody, ntyGenericInst, ntyGenericParam, ntyDistinct, ntyEnum, ntyOrdinal, ntyArray, ntyObject, ntyTuple, ntySet, ntyRange, ntyPtr, ntyRef, ntyVar, ntySequence, ntyProc, ntyPointer, ntyOpenArray, ntyString, ntyCString, ntyForward, ntyInt, ntyInt8, ntyInt16, ntyInt32, ntyInt64, ntyFloat, ntyFloat32, ntyFloat64, ntyFloat128, ntyUInt, ntyUInt8, ntyUInt16, ntyUInt32, ntyUInt64, ntyUnused0, ntyUnused1, ntyUnused2, ntyVarargs, ntyUncheckedArray, ntyError, ntyBuiltinTypeClass, ntyUserTypeClass, ntyUserTypeClassInst, ntyCompositeTypeClass, ntyInferred, ntyAnd, ntyOr, ntyNot, ntyAnything, ntyStatic, ntyFromExpr, ntyOpt, ntyVoid TNimTypeKinds* {.deprecated.} = set[NimTypeKind] NimSymKind* = enum nskUnknown, nskConditional, nskDynLib, nskParam, nskGenericParam, nskTemp, nskModule, nskType, nskVar, nskLet, nskConst, nskResult, nskProc, nskFunc, nskMethod, nskIterator, nskConverter, nskMacro, nskTemplate, nskField, nskEnumField, nskForVar, nskLabel, nskStub TNimSymKinds* {.deprecated.} = set[NimSymKind] type NimIdent* {.deprecated.} = object of RootObj ## Represents a Nim identifier in the AST. **Note**: This is only ## rarely useful, for identifier construction from a string ## use ``ident"abc"``. NimSymObj = object # hidden NimSym* {.deprecated.} = ref NimSymObj ## Represents a Nim *symbol* in the compiler; a *symbol* is a looked-up ## *ident*. const nnkLiterals* = {nnkCharLit..nnkNilLit} nnkCallKinds* = {nnkCall, nnkInfix, nnkPrefix, nnkPostfix, nnkCommand, nnkCallStrLit} nnkPragmaCallKinds = {nnkExprColonExpr, nnkCall, nnkCallStrLit} {.push warnings: off.} proc `!`*(s: string): NimIdent {.magic: "StrToIdent", noSideEffect, deprecated: "Deprecated since version 0.18.0: Use 'ident' or 'newIdentNode' instead.".} ## Constructs an identifier from the string `s`. proc toNimIdent*(s: string): NimIdent {.magic: "StrToIdent", noSideEffect, deprecated: "Deprecated since version 0.18.0: Use 'ident' or 'newIdentNode' instead.".} ## Constructs an identifier from the string `s`. proc `==`*(a, b: NimIdent): bool {.magic: "EqIdent", noSideEffect, deprecated: "Deprecated since version 0.18.1; Use '==' on 'NimNode' instead.".} ## Compares two Nim identifiers. proc `==`*(a, b: NimNode): bool {.magic: "EqNimrodNode", noSideEffect.} ## Compare two Nim nodes. Return true if nodes are structurally ## equivalent. This means two independently created nodes can be equal. proc `==`*(a, b: NimSym): bool {.magic: "EqNimrodNode", noSideEffect, deprecated: "Deprecated since version 0.18.1; Use '==(NimNode, NimNode)' instead.".} ## Compares two Nim symbols. {.pop.} proc sameType*(a, b: NimNode): bool {.magic: "SameNodeType", noSideEffect.} = ## Compares two Nim nodes' types. Return true if the types are the same, ## eg. true when comparing alias with original type. discard proc len*(n: NimNode): int {.magic: "NLen", noSideEffect.} ## Returns the number of children of `n`. proc `[]`*(n: NimNode, i: int): NimNode {.magic: "NChild", noSideEffect.} ## Get `n`'s `i`'th child. proc `[]`*(n: NimNode, i: BackwardsIndex): NimNode = n[n.len - i.int] ## Get `n`'s `i`'th child. template `^^`(n: NimNode, i: untyped): untyped = (when i is BackwardsIndex: n.len - int(i) else: int(i)) proc `[]`*[T, U](n: NimNode, x: HSlice[T, U]): seq[NimNode] = ## Slice operation for NimNode. ## Returns a seq of child of `n` who inclusive range [n[x.a], n[x.b]]. let xa = n ^^ x.a let L = (n ^^ x.b) - xa + 1 result = newSeq[NimNode](L) for i in 0.. NimNode` instead".} when defined(nimSymKind): proc symKind*(symbol: NimNode): NimSymKind {.magic: "NSymKind", noSideEffect.} proc getImpl*(symbol: NimNode): NimNode {.magic: "GetImpl", noSideEffect.} ## Returns a copy of the declaration of a symbol or `nil`. proc strVal*(n: NimNode): string {.magic: "NStrVal", noSideEffect.} ## Returns the string value of an identifier, symbol, comment, or string literal. ## ## See also: ## * `strVal= proc<#strVal=,NimNode,string>`_ for setting the string value. proc `$`*(i: NimIdent): string {.magic: "NStrVal", noSideEffect, deprecated: "Deprecated since version 0.18.1; Use 'strVal' instead.".} ## Converts a Nim identifier to a string. proc `$`*(s: NimSym): string {.magic: "NStrVal", noSideEffect, deprecated: "Deprecated since version 0.18.1; Use 'strVal' instead.".} ## Converts a Nim symbol to a string. else: # bootstrapping substitute proc getImpl*(symbol: NimNode): NimNode = symbol.symbol.getImpl proc strValOld(n: NimNode): string {.magic: "NStrVal", noSideEffect.} proc `$`*(s: NimSym): string {.magic: "IdentToStr", noSideEffect.} proc `$`*(i: NimIdent): string {.magic: "IdentToStr", noSideEffect.} proc strVal*(n: NimNode): string = if n.kind == nnkIdent: $n.ident elif n.kind == nnkSym: $n.symbol else: n.strValOld {.pop.} when defined(nimSymImplTransform): proc getImplTransformed*(symbol: NimNode): NimNode {.magic: "GetImplTransf", noSideEffect.} ## For a typed proc returns the AST after transformation pass. when defined(nimHasSymOwnerInMacro): proc owner*(sym: NimNode): NimNode {.magic: "SymOwner", noSideEffect.} ## Accepts a node of kind `nnkSym` and returns its owner's symbol. ## The meaning of 'owner' depends on `sym`'s `NimSymKind` and declaration ## context. For top level declarations this is an `nskModule` symbol, ## for proc local variables an `nskProc` symbol, for enum/object fields an ## `nskType` symbol, etc. For symbols without an owner, `nil` is returned. ## ## See also: ## * `symKind proc<#symKind,NimNode>`_ to get the kind of a symbol ## * `getImpl proc<#getImpl,NimNode>`_ to get the declaration of a symbol when defined(nimHasInstantiationOfInMacro): proc isInstantiationOf*(instanceProcSym, genProcSym: NimNode): bool {.magic: "SymIsInstantiationOf", noSideEffect.} ## Checks if a proc symbol is an instance of the generic proc symbol. ## Useful to check proc symbols against generic symbols ## returned by `bindSym`. proc getType*(n: NimNode): NimNode {.magic: "NGetType", noSideEffect.} ## With 'getType' you can access the node's `type`:idx:. A Nim type is ## mapped to a Nim AST too, so it's slightly confusing but it means the same ## API can be used to traverse types. Recursive types are flattened for you ## so there is no danger of infinite recursions during traversal. To ## resolve recursive types, you have to call 'getType' again. To see what ## kind of type it is, call `typeKind` on getType's result. proc getType*(n: typedesc): NimNode {.magic: "NGetType", noSideEffect.} ## Version of ``getType`` which takes a ``typedesc``. proc typeKind*(n: NimNode): NimTypeKind {.magic: "NGetType", noSideEffect.} ## Returns the type kind of the node 'n' that should represent a type, that ## means the node should have been obtained via ``getType``. proc getTypeInst*(n: NimNode): NimNode {.magic: "NGetType", noSideEffect.} = ## Returns the `type`:idx: of a node in a form matching the way the ## type instance was declared in the code. runnableExamples: type Vec[N: static[int], T] = object arr: array[N, T] Vec4[T] = Vec[4, T] Vec4f = Vec4[float32] var a: Vec4f var b: Vec4[float32] var c: Vec[4, float32] macro dumpTypeInst(x: typed): untyped = newLit(x.getTypeInst.repr) doAssert(dumpTypeInst(a) == "Vec4f") doAssert(dumpTypeInst(b) == "Vec4[float32]") doAssert(dumpTypeInst(c) == "Vec[4, float32]") proc getTypeInst*(n: typedesc): NimNode {.magic: "NGetType", noSideEffect.} ## Version of ``getTypeInst`` which takes a ``typedesc``. proc getTypeImpl*(n: NimNode): NimNode {.magic: "NGetType", noSideEffect.} = ## Returns the `type`:idx: of a node in a form matching the implementation ## of the type. Any intermediate aliases are expanded to arrive at the final ## type implementation. You can instead use ``getImpl`` on a symbol if you ## want to find the intermediate aliases. runnableExamples: type Vec[N: static[int], T] = object arr: array[N, T] Vec4[T] = Vec[4, T] Vec4f = Vec4[float32] var a: Vec4f var b: Vec4[float32] var c: Vec[4, float32] macro dumpTypeImpl(x: typed): untyped = newLit(x.getTypeImpl.repr) let t = """ object arr: array[0 .. 3, float32] """ doAssert(dumpTypeImpl(a) == t) doAssert(dumpTypeImpl(b) == t) doAssert(dumpTypeImpl(c) == t) when defined(nimHasSignatureHashInMacro): proc signatureHash*(n: NimNode): string {.magic: "NSigHash", noSideEffect.} ## Returns a stable identifier derived from the signature of a symbol. ## The signature combines many factors such as the type of the symbol, ## the owning module of the symbol and others. The same identifier is ## used in the back-end to produce the mangled symbol name. proc symBodyHash*(s: NimNode): string {.noSideEffect.} = ## Returns a stable digest for symbols derived not only from type signature ## and owning module, but also implementation body. All procs/variables used in ## the implementation of this symbol are hashed recursively as well, including ## magics from system module. discard proc getTypeImpl*(n: typedesc): NimNode {.magic: "NGetType", noSideEffect.} ## Version of ``getTypeImpl`` which takes a ``typedesc``. proc `intVal=`*(n: NimNode, val: BiggestInt) {.magic: "NSetIntVal", noSideEffect.} proc `floatVal=`*(n: NimNode, val: BiggestFloat) {.magic: "NSetFloatVal", noSideEffect.} {.push warnings: off.} proc `symbol=`*(n: NimNode, val: NimSym) {.magic: "NSetSymbol", noSideEffect, deprecated: "Deprecated since version 0.18.1; Generate a new 'NimNode' with 'genSym' instead.".} proc `ident=`*(n: NimNode, val: NimIdent) {.magic: "NSetIdent", noSideEffect, deprecated: "Deprecated since version 0.18.1; Generate a new 'NimNode' with 'ident(string)' instead.".} {.pop.} #proc `typ=`*(n: NimNode, typ: typedesc) {.magic: "NSetType".} # this is not sound! Unfortunately forbidding 'typ=' is not enough, as you # can easily do: # let bracket = semCheck([1, 2]) # let fake = semCheck(2.0) # bracket[0] = fake # constructs a mixed array with ints and floats! proc `strVal=`*(n: NimNode, val: string) {.magic: "NSetStrVal", noSideEffect.} ## Sets the string value of a string literal or comment. ## Setting `strVal` is disallowed for `nnkIdent` and `nnkSym` nodes; a new node ## must be created using `ident` or `bindSym` instead. ## ## See also: ## * `strVal proc<#strVal,NimNode>`_ for getting the string value. ## * `ident proc<#ident,string>`_ for creating an identifier. ## * `bindSym proc<#bindSym%2C%2CBindSymRule>`_ for binding a symbol. proc newNimNode*(kind: NimNodeKind, lineInfoFrom: NimNode = nil): NimNode {.magic: "NNewNimNode", noSideEffect.} ## Creates a new AST node of the specified kind. ## ## The ``lineInfoFrom`` parameter is used for line information when the ## produced code crashes. You should ensure that it is set to a node that ## you are transforming. proc copyNimNode*(n: NimNode): NimNode {.magic: "NCopyNimNode", noSideEffect.} proc copyNimTree*(n: NimNode): NimNode {.magic: "NCopyNimTree", noSideEffect.} proc error*(msg: string, n: NimNode = nil) {.magic: "NError", benign.} ## Writes an error message at compile time. The optional ``n: NimNode`` ## parameter is used as the source for file and line number information in ## the compilation error message. proc warning*(msg: string, n: NimNode = nil) {.magic: "NWarning", benign.} ## Writes a warning message at compile time. proc hint*(msg: string, n: NimNode = nil) {.magic: "NHint", benign.} ## Writes a hint message at compile time. proc newStrLitNode*(s: string): NimNode {.compileTime, noSideEffect.} = ## Creates a string literal node from `s`. result = newNimNode(nnkStrLit) result.strVal = s proc newCommentStmtNode*(s: string): NimNode {.compileTime, noSideEffect.} = ## Creates a comment statement node. result = newNimNode(nnkCommentStmt) result.strVal = s proc newIntLitNode*(i: BiggestInt): NimNode {.compileTime.} = ## Creates an int literal node from `i`. result = newNimNode(nnkIntLit) result.intVal = i proc newFloatLitNode*(f: BiggestFloat): NimNode {.compileTime.} = ## Creates a float literal node from `f`. result = newNimNode(nnkFloatLit) result.floatVal = f {.push warnings: off.} proc newIdentNode*(i: NimIdent): NimNode {.compileTime, deprecated.} = ## Creates an identifier node from `i`. result = newNimNode(nnkIdent) result.ident = i {.pop.} proc newIdentNode*(i: string): NimNode {.magic: "StrToIdent", noSideEffect, compilerproc.} ## Creates an identifier node from `i`. It is simply an alias for ## ``ident(string)``. Use that, it's shorter. type BindSymRule* = enum ## specifies how ``bindSym`` behaves brClosed, ## only the symbols in current scope are bound brOpen, ## open wrt overloaded symbols, but may be a single ## symbol if not ambiguous (the rules match that of ## binding in generics) brForceOpen ## same as brOpen, but it will always be open even ## if not ambiguous (this cannot be achieved with ## any other means in the language currently) proc bindSym*(ident: string | NimNode, rule: BindSymRule = brClosed): NimNode {. magic: "NBindSym", noSideEffect.} ## Ceates a node that binds `ident` to a symbol node. The bound symbol ## may be an overloaded symbol. ## if `ident` is a NimNode, it must have ``nnkIdent`` kind. ## If ``rule == brClosed`` either an ``nnkClosedSymChoice`` tree is ## returned or ``nnkSym`` if the symbol is not ambiguous. ## If ``rule == brOpen`` either an ``nnkOpenSymChoice`` tree is ## returned or ``nnkSym`` if the symbol is not ambiguous. ## If ``rule == brForceOpen`` always an ``nnkOpenSymChoice`` tree is ## returned even if the symbol is not ambiguous. ## ## Experimental feature: ## use {.experimental: "dynamicBindSym".} to activate it. ## If called from template / regular code, `ident` and `rule` must be ## constant expression / literal value. ## If called from macros / compile time procs / static blocks, ## `ident` and `rule` can be VM computed value. proc genSym*(kind: NimSymKind = nskLet; ident = ""): NimNode {. magic: "NGenSym", noSideEffect.} ## Generates a fresh symbol that is guaranteed to be unique. The symbol ## needs to occur in a declaration context. proc callsite*(): NimNode {.magic: "NCallSite", benign, deprecated: "Deprecated since v0.18.1; use varargs[untyped] in the macro prototype instead".} ## Returns the AST of the invocation expression that invoked this macro. proc toStrLit*(n: NimNode): NimNode {.compileTime.} = ## Converts the AST `n` to the concrete Nim code and wraps that ## in a string literal node. return newStrLitNode(repr(n)) type LineInfo* = object filename*: string line*,column*: int proc `$`*(arg: LineInfo): string = ## Return a string representation in the form `filepath(line, column)`. # BUG: without `result = `, gives compile error result = arg.filename & "(" & $arg.line & ", " & $arg.column & ")" #proc lineinfo*(n: NimNode): LineInfo {.magic: "NLineInfo", noSideEffect.} # ## returns the position the node appears in the original source file # ## in the form filename(line, col) proc getLine(arg: NimNode): int {.magic: "NLineInfo", noSideEffect.} proc getColumn(arg: NimNode): int {.magic: "NLineInfo", noSideEffect.} proc getFile(arg: NimNode): string {.magic: "NLineInfo", noSideEffect.} proc copyLineInfo*(arg: NimNode, info: NimNode) {.magic: "NLineInfo", noSideEffect.} ## Copy lineinfo from ``info``. proc lineInfoObj*(n: NimNode): LineInfo {.compileTime.} = ## Returns ``LineInfo`` of ``n``, using absolute path for ``filename``. result.filename = n.getFile result.line = n.getLine result.column = n.getColumn proc lineInfo*(arg: NimNode): string {.compileTime.} = ## Return line info in the form `filepath(line, column)`. $arg.lineInfoObj proc internalParseExpr(s: string): NimNode {. magic: "ParseExprToAst", noSideEffect.} proc internalParseStmt(s: string): NimNode {. magic: "ParseStmtToAst", noSideEffect.} proc internalErrorFlag*(): string {.magic: "NError", noSideEffect.} ## Some builtins set an error flag. This is then turned into a proper ## exception. **Note**: Ordinary application code should not call this. proc parseExpr*(s: string): NimNode {.noSideEffect, compileTime.} = ## Compiles the passed string to its AST representation. ## Expects a single expression. Raises ``ValueError`` for parsing errors. result = internalParseExpr(s) let x = internalErrorFlag() if x.len > 0: raise newException(ValueError, x) proc parseStmt*(s: string): NimNode {.noSideEffect, compileTime.} = ## Compiles the passed string to its AST representation. ## Expects one or more statements. Raises ``ValueError`` for parsing errors. result = internalParseStmt(s) let x = internalErrorFlag() if x.len > 0: raise newException(ValueError, x) proc getAst*(macroOrTemplate: untyped): NimNode {.magic: "ExpandToAst", noSideEffect.} ## Obtains the AST nodes returned from a macro or template invocation. ## Example: ## ## .. code-block:: nim ## ## macro FooMacro() = ## var ast = getAst(BarTemplate()) proc quote*(bl: typed, op = "``"): NimNode {.magic: "QuoteAst", noSideEffect.} ## Quasi-quoting operator. ## Accepts an expression or a block and returns the AST that represents it. ## Within the quoted AST, you are able to interpolate NimNode expressions ## from the surrounding scope. If no operator is given, quoting is done using ## backticks. Otherwise, the given operator must be used as a prefix operator ## for any interpolated expression. ## ## Example: ## ## .. code-block:: nim ## ## macro check(ex: untyped) = ## # this is a simplified version of the check macro from the ## # unittest module. ## ## # If there is a failed check, we want to make it easy for ## # the user to jump to the faulty line in the code, so we ## # get the line info here: ## var info = ex.lineinfo ## ## # We will also display the code string of the failed check: ## var expString = ex.toStrLit ## ## # Finally we compose the code to implement the check: ## result = quote do: ## if not `ex`: ## echo `info` & ": Check failed: " & `expString` proc expectKind*(n: NimNode, k: NimNodeKind) {.compileTime.} = ## Checks that `n` is of kind `k`. If this is not the case, ## compilation aborts with an error message. This is useful for writing ## macros that check the AST that is passed to them. if n.kind != k: error("Expected a node of kind " & $k & ", got " & $n.kind, n) proc expectMinLen*(n: NimNode, min: int) {.compileTime.} = ## Checks that `n` has at least `min` children. If this is not the case, ## compilation aborts with an error message. This is useful for writing ## macros that check its number of arguments. if n.len < min: error("macro expects a node with " & $min & " children", n) proc expectLen*(n: NimNode, len: int) {.compileTime.} = ## Checks that `n` has exactly `len` children. If this is not the case, ## compilation aborts with an error message. This is useful for writing ## macros that check its number of arguments. if n.len != len: error("macro expects a node with " & $len & " children", n) proc expectLen*(n: NimNode, min, max: int) {.compileTime.} = ## Checks that `n` has a number of children in the range ``min..max``. ## If this is not the case, compilation aborts with an error message. ## This is useful for writing macros that check its number of arguments. if n.len < min or n.len > max: error("macro expects a node with " & $min & ".." & $max & " children", n) proc newTree*(kind: NimNodeKind, children: varargs[NimNode]): NimNode {.compileTime.} = ## Produces a new node with children. result = newNimNode(kind) result.add(children) proc newCall*(theProc: NimNode, args: varargs[NimNode]): NimNode {.compileTime.} = ## Produces a new call node. `theProc` is the proc that is called with ## the arguments ``args[0..]``. result = newNimNode(nnkCall) result.add(theProc) result.add(args) {.push warnings: off.} proc newCall*(theProc: NimIdent, args: varargs[NimNode]): NimNode {.compileTime, deprecated: "Deprecated since v0.18.1; use 'newCall(string, ...)' or 'newCall(NimNode, ...)' instead".} = ## Produces a new call node. `theProc` is the proc that is called with ## the arguments ``args[0..]``. result = newNimNode(nnkCall) result.add(newIdentNode(theProc)) result.add(args) {.pop.} proc newCall*(theProc: string, args: varargs[NimNode]): NimNode {.compileTime.} = ## Produces a new call node. `theProc` is the proc that is called with ## the arguments ``args[0..]``. result = newNimNode(nnkCall) result.add(newIdentNode(theProc)) result.add(args) proc newLit*(c: char): NimNode {.compileTime.} = ## Produces a new character literal node. result = newNimNode(nnkCharLit) result.intVal = ord(c) proc newLit*(i: int): NimNode {.compileTime.} = ## Produces a new integer literal node. result = newNimNode(nnkIntLit) result.intVal = i proc newLit*(i: int8): NimNode {.compileTime.} = ## Produces a new integer literal node. result = newNimNode(nnkInt8Lit) result.intVal = i proc newLit*(i: int16): NimNode {.compileTime.} = ## Produces a new integer literal node. result = newNimNode(nnkInt16Lit) result.intVal = i proc newLit*(i: int32): NimNode {.compileTime.} = ## Produces a new integer literal node. result = newNimNode(nnkInt32Lit) result.intVal = i proc newLit*(i: int64): NimNode {.compileTime.} = ## Produces a new integer literal node. result = newNimNode(nnkInt64Lit) result.intVal = i proc newLit*(i: uint): NimNode {.compileTime.} = ## Produces a new unsigned integer literal node. result = newNimNode(nnkUIntLit) result.intVal = BiggestInt(i) proc newLit*(i: uint8): NimNode {.compileTime.} = ## Produces a new unsigned integer literal node. result = newNimNode(nnkUInt8Lit) result.intVal = BiggestInt(i) proc newLit*(i: uint16): NimNode {.compileTime.} = ## Produces a new unsigned integer literal node. result = newNimNode(nnkUInt16Lit) result.intVal = BiggestInt(i) proc newLit*(i: uint32): NimNode {.compileTime.} = ## Produces a new unsigned integer literal node. result = newNimNode(nnkUInt32Lit) result.intVal = BiggestInt(i) proc newLit*(i: uint64): NimNode {.compileTime.} = ## Produces a new unsigned integer literal node. result = newNimNode(nnkUInt64Lit) result.intVal = BiggestInt(i) proc newLit*(b: bool): NimNode {.compileTime.} = ## Produces a new boolean literal node. result = if b: bindSym"true" else: bindSym"false" proc newLit*(s: string): NimNode {.compileTime.} = ## Produces a new string literal node. result = newNimNode(nnkStrLit) result.strVal = s when false: # the float type is not really a distinct type as described in https://github.com/nim-lang/Nim/issues/5875 proc newLit*(f: float): NimNode {.compileTime.} = ## Produces a new float literal node. result = newNimNode(nnkFloatLit) result.floatVal = f proc newLit*(f: float32): NimNode {.compileTime.} = ## Produces a new float literal node. result = newNimNode(nnkFloat32Lit) result.floatVal = f proc newLit*(f: float64): NimNode {.compileTime.} = ## Produces a new float literal node. result = newNimNode(nnkFloat64Lit) result.floatVal = f when declared(float128): proc newLit*(f: float128): NimNode {.compileTime.} = ## Produces a new float literal node. result = newNimNode(nnkFloat128Lit) result.floatVal = f proc newLit*(arg: enum): NimNode {.compileTime.} = result = newCall( arg.type.getTypeInst[1], newLit(int(arg)) ) proc newLit*[N,T](arg: array[N,T]): NimNode {.compileTime.} proc newLit*[T](arg: seq[T]): NimNode {.compileTime.} proc newLit*[T](s: set[T]): NimNode {.compileTime.} proc newLit*(arg: tuple): NimNode {.compileTime.} proc newLit*(arg: object): NimNode {.compileTime.} = result = nnkObjConstr.newTree(arg.type.getTypeInst[1]) for a, b in arg.fieldPairs: result.add nnkExprColonExpr.newTree( newIdentNode(a), newLit(b) ) proc newLit*(arg: ref object): NimNode {.compileTime.} = ## produces a new ref type literal node. result = nnkObjConstr.newTree(arg.type.getTypeInst[1]) for a, b in fieldPairs(arg[]): result.add nnkExprColonExpr.newTree(newIdentNode(a), newLit(b)) proc newLit*[N,T](arg: array[N,T]): NimNode {.compileTime.} = result = nnkBracket.newTree for x in arg: result.add newLit(x) proc newLit*[T](arg: seq[T]): NimNode {.compileTime.} = let bracket = nnkBracket.newTree for x in arg: bracket.add newLit(x) result = nnkPrefix.newTree( bindSym"@", bracket ) if arg.len == 0: # add type cast for empty seq var typ = getTypeInst(typeof(arg))[1] result = newCall(typ,result) proc newLit*[T](s: set[T]): NimNode {.compileTime.} = result = nnkCurly.newTree for x in s: result.add newLit(x) proc newLit*(arg: tuple): NimNode {.compileTime.} = result = nnkPar.newTree for a,b in arg.fieldPairs: result.add nnkExprColonExpr.newTree(newIdentNode(a), newLit(b)) proc nestList*(op: NimNode; pack: NimNode): NimNode {.compileTime.} = ## Nests the list `pack` into a tree of call expressions: ## ``[a, b, c]`` is transformed into ``op(a, op(c, d))``. ## This is also known as fold expression. if pack.len < 1: error("`nestList` expects a node with at least 1 child") result = pack[^1] for i in countdown(pack.len - 2, 0): result = newCall(op, pack[i], result) proc nestList*(op: NimNode; pack: NimNode; init: NimNode): NimNode {.compileTime.} = ## Nests the list `pack` into a tree of call expressions: ## ``[a, b, c]`` is transformed into ``op(a, op(c, d))``. ## This is also known as fold expression. result = init for i in countdown(pack.len - 1, 0): result = newCall(op, pack[i], result) {.push warnings: off.} proc nestList*(theProc: NimIdent, x: NimNode): NimNode {.compileTime, deprecated: "Deprecated since v0.18.1; use one of 'nestList(NimNode, ...)' instead.".} = nestList(newIdentNode(theProc), x) {.pop.} proc treeTraverse(n: NimNode; res: var string; level = 0; isLisp = false, indented = false) {.benign.} = if level > 0: if indented: res.add("\n") for i in 0 .. level-1: if isLisp: res.add(" ") # dumpLisp indentation else: res.add(" ") # dumpTree indentation else: res.add(" ") if isLisp: res.add("(") res.add(($n.kind).substr(3)) case n.kind of nnkEmpty, nnkNilLit: discard # same as nil node in this representation of nnkCharLit .. nnkInt64Lit: res.add(" " & $n.intVal) of nnkFloatLit .. nnkFloat64Lit: res.add(" " & $n.floatVal) of nnkStrLit .. nnkTripleStrLit, nnkCommentStmt, nnkIdent, nnkSym: res.add(" " & $n.strVal.newLit.repr) of nnkNone: assert false else: for j in 0 .. n.len-1: n[j].treeTraverse(res, level+1, isLisp, indented) if isLisp: res.add(")") proc treeRepr*(n: NimNode): string {.compileTime, benign.} = ## Convert the AST `n` to a human-readable tree-like string. ## ## See also `repr`, `lispRepr`, and `astGenRepr`. n.treeTraverse(result, isLisp = false, indented = true) proc lispRepr*(n: NimNode; indented = false): string {.compileTime, benign.} = ## Convert the AST ``n`` to a human-readable lisp-like string. ## ## See also ``repr``, ``treeRepr``, and ``astGenRepr``. n.treeTraverse(result, isLisp = true, indented = indented) proc astGenRepr*(n: NimNode): string {.compileTime, benign.} = ## Convert the AST ``n`` to the code required to generate that AST. ## ## See also ``repr``, ``treeRepr``, and ``lispRepr``. const NodeKinds = {nnkEmpty, nnkIdent, nnkSym, nnkNone, nnkCommentStmt} LitKinds = {nnkCharLit..nnkInt64Lit, nnkFloatLit..nnkFloat64Lit, nnkStrLit..nnkTripleStrLit} proc traverse(res: var string, level: int, n: NimNode) {.benign.} = for i in 0..level-1: res.add " " if n.kind in NodeKinds: res.add("new" & ($n.kind).substr(3) & "Node(") elif n.kind in LitKinds: res.add("newLit(") elif n.kind == nnkNilLit: res.add("newNilLit()") else: res.add($n.kind) case n.kind of nnkEmpty, nnkNilLit: discard of nnkCharLit: res.add("'" & $chr(n.intVal) & "'") of nnkIntLit..nnkInt64Lit: res.add($n.intVal) of nnkFloatLit..nnkFloat64Lit: res.add($n.floatVal) of nnkStrLit..nnkTripleStrLit, nnkCommentStmt, nnkIdent, nnkSym: res.add(n.strVal.newLit.repr) of nnkNone: assert false else: res.add(".newTree(") for j in 0.. `a.b` return newNimNode(nnkDotExpr).add(a, b) proc newColonExpr*(a, b: NimNode): NimNode {.compileTime.} = ## Create new colon expression. ## newColonExpr(a, b) -> `a: b` newNimNode(nnkExprColonExpr).add(a, b) proc newIdentDefs*(name, kind: NimNode; default = newEmptyNode()): NimNode {.compileTime.} = ## Creates a new ``nnkIdentDefs`` node of a specific kind and value. ## ## ``nnkIdentDefs`` need to have at least three children, but they can have ## more: first comes a list of identifiers followed by a type and value ## nodes. This helper proc creates a three node subtree, the first subnode ## being a single identifier name. Both the ``kind`` node and ``default`` ## (value) nodes may be empty depending on where the ``nnkIdentDefs`` ## appears: tuple or object definitions will have an empty ``default`` node, ## ``let`` or ``var`` blocks may have an empty ``kind`` node if the ## identifier is being assigned a value. Example: ## ## .. code-block:: nim ## ## var varSection = newNimNode(nnkVarSection).add( ## newIdentDefs(ident("a"), ident("string")), ## newIdentDefs(ident("b"), newEmptyNode(), newLit(3))) ## # --> var ## # a: string ## # b = 3 ## ## If you need to create multiple identifiers you need to use the lower level ## ``newNimNode``: ## ## .. code-block:: nim ## ## result = newNimNode(nnkIdentDefs).add( ## ident("a"), ident("b"), ident("c"), ident("string"), ## newStrLitNode("Hello")) newNimNode(nnkIdentDefs).add(name, kind, default) proc newNilLit*(): NimNode {.compileTime.} = ## New nil literal shortcut. result = newNimNode(nnkNilLit) proc last*(node: NimNode): NimNode {.compileTime.} = node[node.len-1] ## Return the last item in nodes children. Same as `node[^1]`. const RoutineNodes* = {nnkProcDef, nnkFuncDef, nnkMethodDef, nnkDo, nnkLambda, nnkIteratorDef, nnkTemplateDef, nnkConverterDef} AtomicNodes* = {nnkNone..nnkNilLit} CallNodes* = {nnkCall, nnkInfix, nnkPrefix, nnkPostfix, nnkCommand, nnkCallStrLit, nnkHiddenCallConv} proc expectKind*(n: NimNode; k: set[NimNodeKind]) {.compileTime.} = ## Checks that `n` is of kind `k`. If this is not the case, ## compilation aborts with an error message. This is useful for writing ## macros that check the AST that is passed to them. if n.kind notin k: error("Expected one of " & $k & ", got " & $n.kind, n) proc newProc*(name = newEmptyNode(); params: openArray[NimNode] = [newEmptyNode()]; body: NimNode = newStmtList(); procType = nnkProcDef; pragmas: NimNode = newEmptyNode()): NimNode {.compileTime.} = ## Shortcut for creating a new proc. ## ## The ``params`` array must start with the return type of the proc, ## followed by a list of IdentDefs which specify the params. if procType notin RoutineNodes: error("Expected one of " & $RoutineNodes & ", got " & $procType) pragmas.expectKind({nnkEmpty, nnkPragma}) result = newNimNode(procType).add( name, newEmptyNode(), newEmptyNode(), newNimNode(nnkFormalParams).add(params), pragmas, newEmptyNode(), body) proc newIfStmt*(branches: varargs[tuple[cond, body: NimNode]]): NimNode {.compileTime.} = ## Constructor for ``if`` statements. ## ## .. code-block:: nim ## ## newIfStmt( ## (Ident, StmtList), ## ... ## ) ## result = newNimNode(nnkIfStmt) if len(branches) < 1: error("If statement must have at least one branch") for i in branches: result.add(newTree(nnkElifBranch, i.cond, i.body)) proc newEnum*(name: NimNode, fields: openArray[NimNode], public, pure: bool): NimNode {.compileTime.} = ## Creates a new enum. `name` must be an ident. Fields are allowed to be ## either idents or EnumFieldDef ## ## .. code-block:: nim ## ## newEnum( ## name = ident("Colors"), ## fields = [ident("Blue"), ident("Red")], ## public = true, pure = false) ## ## # type Colors* = Blue Red ## expectKind name, nnkIdent if len(fields) < 1: error("Enum must contain at least one field") for field in fields: expectKind field, {nnkIdent, nnkEnumFieldDef} let enumBody = newNimNode(nnkEnumTy).add(newEmptyNode()).add(fields) var typeDefArgs = [name, newEmptyNode(), enumBody] if public: let postNode = newNimNode(nnkPostfix).add( newIdentNode("*"), typeDefArgs[0]) typeDefArgs[0] = postNode if pure: let pragmaNode = newNimNode(nnkPragmaExpr).add( typeDefArgs[0], add(newNimNode(nnkPragma), newIdentNode("pure"))) typeDefArgs[0] = pragmaNode let typeDef = add(newNimNode(nnkTypeDef), typeDefArgs) typeSect = add(newNimNode(nnkTypeSection), typeDef) return typeSect proc copyChildrenTo*(src, dest: NimNode) {.compileTime.}= ## Copy all children from `src` to `dest`. for i in 0 ..< src.len: dest.add src[i].copyNimTree template expectRoutine(node: NimNode) = expectKind(node, RoutineNodes) proc name*(someProc: NimNode): NimNode {.compileTime.} = someProc.expectRoutine result = someProc[0] if result.kind == nnkPostfix: if result[1].kind == nnkAccQuoted: result = result[1][0] else: result = result[1] elif result.kind == nnkAccQuoted: result = result[0] proc `name=`*(someProc: NimNode; val: NimNode) {.compileTime.} = someProc.expectRoutine if someProc[0].kind == nnkPostfix: someProc[0][1] = val else: someProc[0] = val proc params*(someProc: NimNode): NimNode {.compileTime.} = someProc.expectRoutine result = someProc[3] proc `params=`* (someProc: NimNode; params: NimNode) {.compileTime.}= someProc.expectRoutine expectKind(params, nnkFormalParams) someProc[3] = params proc pragma*(someProc: NimNode): NimNode {.compileTime.} = ## Get the pragma of a proc type. ## These will be expanded. if someProc.kind == nnkProcTy: result = someProc[1] else: someProc.expectRoutine result = someProc[4] proc `pragma=`*(someProc: NimNode; val: NimNode) {.compileTime.}= ## Set the pragma of a proc type. expectKind(val, {nnkEmpty, nnkPragma}) if someProc.kind == nnkProcTy: someProc[1] = val else: someProc.expectRoutine someProc[4] = val proc addPragma*(someProc, pragma: NimNode) {.compileTime.} = ## Adds pragma to routine definition. someProc.expectKind(RoutineNodes + {nnkProcTy}) var pragmaNode = someProc.pragma if pragmaNode.isNil or pragmaNode.kind == nnkEmpty: pragmaNode = newNimNode(nnkPragma) someProc.pragma = pragmaNode pragmaNode.add(pragma) template badNodeKind(n, f) = error("Invalid node kind " & $n.kind & " for macros.`" & $f & "`", n) proc body*(someProc: NimNode): NimNode {.compileTime.} = case someProc.kind: of RoutineNodes: return someProc[6] of nnkBlockStmt, nnkWhileStmt: return someProc[1] of nnkForStmt: return someProc.last else: badNodeKind someProc, "body" proc `body=`*(someProc: NimNode, val: NimNode) {.compileTime.} = case someProc.kind of RoutineNodes: someProc[6] = val of nnkBlockStmt, nnkWhileStmt: someProc[1] = val of nnkForStmt: someProc[len(someProc)-1] = val else: badNodeKind someProc, "body=" proc basename*(a: NimNode): NimNode {.compileTime, benign.} proc `$`*(node: NimNode): string {.compileTime.} = ## Get the string of an identifier node. case node.kind of nnkPostfix: result = node.basename.strVal & "*" of nnkStrLit..nnkTripleStrLit, nnkCommentStmt, nnkSym, nnkIdent: result = node.strVal of nnkOpenSymChoice, nnkClosedSymChoice: result = $node[0] of nnkAccQuoted: result = $node[0] else: badNodeKind node, "$" proc ident*(name: string): NimNode {.magic: "StrToIdent", noSideEffect.} ## Create a new ident node from a string. iterator items*(n: NimNode): NimNode {.inline.} = ## Iterates over the children of the NimNode ``n``. for i in 0 ..< n.len: yield n[i] iterator pairs*(n: NimNode): (int, NimNode) {.inline.} = ## Iterates over the children of the NimNode ``n`` and its indices. for i in 0 ..< n.len: yield (i, n[i]) iterator children*(n: NimNode): NimNode {.inline.} = ## Iterates over the children of the NimNode ``n``. for i in 0 ..< n.len: yield n[i] template findChild*(n: NimNode; cond: untyped): NimNode {.dirty.} = ## Find the first child node matching condition (or nil). ## ## .. code-block:: nim ## var res = findChild(n, it.kind == nnkPostfix and ## it.basename.ident == toNimIdent"foo") block: var res: NimNode for it in n.children: if cond: res = it break res proc insert*(a: NimNode; pos: int; b: NimNode) {.compileTime.} = ## Insert node ``b`` into node ``a`` at ``pos``. if len(a)-1 < pos: # add some empty nodes first for i in len(a)-1..pos-2: a.add newEmptyNode() a.add b else: # push the last item onto the list again # and shift each item down to pos up one a.add(a[a.len-1]) for i in countdown(len(a) - 3, pos): a[i + 1] = a[i] a[pos] = b proc basename*(a: NimNode): NimNode = ## Pull an identifier from prefix/postfix expressions. case a.kind of nnkIdent: return a of nnkPostfix, nnkPrefix: return a[1] else: error("Do not know how to get basename of (" & treeRepr(a) & ")\n" & repr(a), a) proc `basename=`*(a: NimNode; val: string) {.compileTime.}= case a.kind of nnkIdent: a.strVal = val of nnkPostfix, nnkPrefix: a[1] = ident(val) else: error("Do not know how to get basename of (" & treeRepr(a) & ")\n" & repr(a), a) proc postfix*(node: NimNode; op: string): NimNode {.compileTime.} = newNimNode(nnkPostfix).add(ident(op), node) proc prefix*(node: NimNode; op: string): NimNode {.compileTime.} = newNimNode(nnkPrefix).add(ident(op), node) proc infix*(a: NimNode; op: string; b: NimNode): NimNode {.compileTime.} = newNimNode(nnkInfix).add(ident(op), a, b) proc unpackPostfix*(node: NimNode): tuple[node: NimNode; op: string] {. compileTime.} = node.expectKind nnkPostfix result = (node[1], $node[0]) proc unpackPrefix*(node: NimNode): tuple[node: NimNode; op: string] {. compileTime.} = node.expectKind nnkPrefix result = (node[1], $node[0]) proc unpackInfix*(node: NimNode): tuple[left: NimNode; op: string; right: NimNode] {.compileTime.} = expectKind(node, nnkInfix) result = (node[1], $node[0], node[2]) proc copy*(node: NimNode): NimNode {.compileTime.} = ## An alias for `copyNimTree<#copyNimTree,NimNode>`_. return node.copyNimTree() when defined(nimVmEqIdent): proc eqIdent*(a: string; b: string): bool {.magic: "EqIdent", noSideEffect.} ## Style insensitive comparison. proc eqIdent*(a: NimNode; b: string): bool {.magic: "EqIdent", noSideEffect.} ## Style insensitive comparison. ``a`` can be an identifier or a ## symbol. ``a`` may be wrapped in an export marker ## (``nnkPostfix``) or quoted with backticks (``nnkAccQuoted``), ## these nodes will be unwrapped. proc eqIdent*(a: string; b: NimNode): bool {.magic: "EqIdent", noSideEffect.} ## Style insensitive comparison. ``b`` can be an identifier or a ## symbol. ``b`` may be wrapped in an export marker ## (``nnkPostfix``) or quoted with backticks (``nnkAccQuoted``), ## these nodes will be unwrapped. proc eqIdent*(a: NimNode; b: NimNode): bool {.magic: "EqIdent", noSideEffect.} ## Style insensitive comparison. ``a`` and ``b`` can be an ## identifier or a symbol. Both may be wrapped in an export marker ## (``nnkPostfix``) or quoted with backticks (``nnkAccQuoted``), ## these nodes will be unwrapped. else: # this procedure is optimized for native code, it should not be compiled to nimVM bytecode. proc cmpIgnoreStyle(a, b: cstring): int {.noSideEffect.} = proc toLower(c: char): char {.inline.} = if c in {'A'..'Z'}: result = chr(ord(c) + (ord('a') - ord('A'))) else: result = c var i = 0 var j = 0 # first char is case sensitive if a[0] != b[0]: return 1 while true: while a[i] == '_': inc(i) while b[j] == '_': inc(j) # BUGFIX: typo var aa = toLower(a[i]) var bb = toLower(b[j]) result = ord(aa) - ord(bb) if result != 0 or aa == '\0': break inc(i) inc(j) proc eqIdent*(a, b: string): bool = cmpIgnoreStyle(a, b) == 0 ## Check if two idents are equal. proc eqIdent*(node: NimNode; s: string): bool {.compileTime.} = ## Check if node is some identifier node (``nnkIdent``, ``nnkSym``, etc.) ## is the same as ``s``. Note that this is the preferred way to check! Most ## other ways like ``node.ident`` are much more error-prone, unfortunately. case node.kind of nnkSym, nnkIdent: result = eqIdent(node.strVal, s) of nnkOpenSymChoice, nnkClosedSymChoice: result = eqIdent($node[0], s) else: result = false proc hasArgOfName*(params: NimNode; name: string): bool {.compileTime.}= ## Search ``nnkFormalParams`` for an argument. expectKind(params, nnkFormalParams) for i in 1 ..< params.len: template node: untyped = params[i] if name.eqIdent( $ node[0]): return true proc addIdentIfAbsent*(dest: NimNode, ident: string) {.compileTime.} = ## Add ``ident`` to ``dest`` if it is not present. This is intended for use ## with pragmas. for node in dest.children: case node.kind of nnkIdent: if ident.eqIdent($node): return of nnkExprColonExpr: if ident.eqIdent($node[0]): return else: discard dest.add(ident(ident)) proc boolVal*(n: NimNode): bool {.compileTime, noSideEffect.} = if n.kind == nnkIntLit: n.intVal != 0 else: n == bindSym"true" # hacky solution for now when defined(nimMacrosGetNodeId): proc nodeID*(n: NimNode): int {.magic: NodeId.} ## Returns the id of ``n``, when the compiler has been compiled ## with the flag ``-d:useNodeids``, otherwise returns ``-1``. This ## proc is for the purpose to debug the compiler only. macro expandMacros*(body: typed): untyped = ## Expands one level of macro - useful for debugging. ## Can be used to inspect what happens when a macro call is expanded, ## without altering its result. ## ## For instance, ## ## .. code-block:: nim ## import future, macros ## ## let ## x = 10 ## y = 20 ## expandMacros: ## dump(x + y) ## ## will actually dump `x + y`, but at the same time will print at ## compile time the expansion of the ``dump`` macro, which in this ## case is ``debugEcho ["x + y", " = ", x + y]``. echo body.toStrLit result = body proc customPragmaNode(n: NimNode): NimNode = expectKind(n, {nnkSym, nnkDotExpr, nnkBracketExpr, nnkTypeOfExpr, nnkCheckedFieldExpr}) let typ = n.getTypeInst() if typ.kind == nnkBracketExpr and typ.len > 1 and typ[1].kind == nnkProcTy: return typ[1][1] elif typ.typeKind == ntyTypeDesc: let impl = typ[1].getImpl() if impl[0].kind == nnkPragmaExpr: return impl[0][1] else: return impl[0] # handle types which don't have macro at all if n.kind == nnkSym: # either an variable or a proc let impl = n.getImpl() if impl.kind in RoutineNodes: return impl.pragma elif impl.kind == nnkIdentDefs and impl[0].kind == nnkPragmaExpr: return impl[0][1] else: let timpl = typ.getImpl() if timpl.len>0 and timpl[0].len>1: return timpl[0][1] else: return timpl if n.kind in {nnkDotExpr, nnkCheckedFieldExpr}: let name = $(if n.kind == nnkCheckedFieldExpr: n[0][1] else: n[1]) let typInst = getTypeInst(if n.kind == nnkCheckedFieldExpr or n[0].kind == nnkHiddenDeref: n[0][0] else: n[0]) var typDef = getImpl(if typInst.kind == nnkVarTy: typInst[0] else: typInst) while typDef != nil: typDef.expectKind(nnkTypeDef) let typ = typDef[2] typ.expectKind({nnkRefTy, nnkPtrTy, nnkObjectTy}) let isRef = typ.kind in {nnkRefTy, nnkPtrTy} if isRef and typ[0].kind in {nnkSym, nnkBracketExpr}: # defines ref type for another object(e.g. X = ref X) typDef = getImpl(typ[0]) else: # object definition, maybe an object directly defined as a ref type let obj = (if isRef: typ[0] else: typ) var identDefsStack = newSeq[NimNode](obj[2].len) for i in 0.. 0: var identDefs = identDefsStack.pop() if identDefs.kind == nnkRecCase: identDefsStack.add(identDefs[0]) for i in 1.. 0 and p[0].kind == nnkSym and p[0] == cp): return newLit(true) return newLit(false) macro getCustomPragmaVal*(n: typed, cp: typed{nkSym}): untyped = ## Expands to value of custom pragma `cp` of expression `n` which is expected ## to be `nnkDotExpr`, a proc or a type. ## ## See also `hasCustomPragma` ## ## .. code-block:: nim ## template serializationKey(key: string) {.pragma.} ## type ## MyObj {.serializationKey: "mo".} = object ## myField {.serializationKey: "mf".}: int ## var o: MyObj ## assert(o.myField.getCustomPragmaVal(serializationKey) == "mf") ## assert(o.getCustomPragmaVal(serializationKey) == "mo") ## assert(MyObj.getCustomPragmaVal(serializationKey) == "mo") let pragmaNode = customPragmaNode(n) for p in pragmaNode: if p.kind in nnkPragmaCallKinds and p.len > 0 and p[0].kind == nnkSym and p[0] == cp: if p.len == 2: result = p[1] else: let def = p[0].getImpl[3] result = newTree(nnkPar) for i in 1 ..< def.len: let key = def[i][0] let val = p[i] result.add newTree(nnkExprColonExpr, key, val) break if result.kind == nnkEmpty: error(n.repr & " doesn't have a pragma named " & cp.repr()) # returning an empty node results in most cases in a cryptic error, when not defined(booting): template emit*(e: static[string]): untyped {.deprecated.} = ## Accepts a single string argument and treats it as nim code ## that should be inserted verbatim in the program ## Example: ## ## .. code-block:: nim ## emit("echo " & '"' & "hello world".toUpper & '"') ## ## Deprecated since version 0.15 since it's so rarely useful. macro payload: untyped {.gensym.} = result = parseStmt(e) payload() macro unpackVarargs*(callee: untyped; args: varargs[untyped]): untyped = result = newCall(callee) for i in 0 ..< args.len: result.add args[i] proc getProjectPath*(): string = discard ## Returns the path to the currently compiling project. ## ## This is not to be confused with `system.currentSourcePath `_ ## which returns the path of the source file containing that template ## call. ## ## For example, assume a ``dir1/foo.nim`` that imports a ``dir2/bar.nim``, ## have the ``bar.nim`` print out both ``getProjectPath`` and ## ``currentSourcePath`` outputs. ## ## Now when ``foo.nim`` is compiled, the ``getProjectPath`` from ## ``bar.nim`` will return the ``dir1/`` path, while the ``currentSourcePath`` ## will return the path to the ``bar.nim`` source file. ## ## Now when ``bar.nim`` is compiled directly, the ``getProjectPath`` ## will now return the ``dir2/`` path, and the ``currentSourcePath`` ## will still return the same path, the path to the ``bar.nim`` source ## file. ## ## The path returned by this proc is set at compile time. ## ## See also: ## * `getCurrentDir proc `_ when defined(nimMacrosSizealignof): proc getSize*(arg: NimNode): int {.magic: "NSizeOf", noSideEffect.} = ## Returns the same result as ``system.sizeof`` if the size is ## known by the Nim compiler. Returns a negative value if the Nim ## compiler does not know the size. proc getAlign*(arg: NimNode): int {.magic: "NSizeOf", noSideEffect.} = ## Returns the same result as ``system.alignof`` if the alignment ## is known by the Nim compiler. It works on ``NimNode`` for use ## in macro context. Returns a negative value if the Nim compiler ## does not know the alignment. proc getOffset*(arg: NimNode): int {.magic: "NSizeOf", noSideEffect.} = ## Returns the same result as ``system.offsetof`` if the offset is ## known by the Nim compiler. It expects a resolved symbol node ## from a field of a type. Therefore it only requires one argument ## instead of two. Returns a negative value if the Nim compiler ## does not know the offset. proc isExported*(n: NimNode): bool {.noSideEffect.} = ## Returns whether the symbol is exported or not.