diff options
Diffstat (limited to 'lib/pure/sugar.nim')
| -rw-r--r-- | lib/pure/sugar.nim | 43 |
1 files changed, 28 insertions, 15 deletions
diff --git a/lib/pure/sugar.nim b/lib/pure/sugar.nim index 239ed9cf1..90ba20c13 100644 --- a/lib/pure/sugar.nim +++ b/lib/pure/sugar.nim @@ -54,6 +54,8 @@ proc createProcType(p, b: NimNode): NimNode = macro `=>`*(p, b: untyped): untyped = ## Syntax sugar for anonymous procedures. It also supports pragmas. + ## + ## .. warning:: Semicolons can not be used to separate procedure arguments. runnableExamples: proc passTwoAndTwo(f: (int, int) -> int): int = f(2, 2) @@ -119,9 +121,9 @@ macro `=>`*(p, b: untyped): untyped = else: error("Incorrect procedure parameter.", c) params.add(identDefs) - of nnkIdent: + of nnkIdent, nnkOpenSymChoice, nnkClosedSymChoice, nnkSym: var identDefs = newNimNode(nnkIdentDefs) - identDefs.add(p) + identDefs.add(ident $p) identDefs.add(ident"auto") identDefs.add(newEmptyNode()) params.add(identDefs) @@ -133,6 +135,8 @@ macro `=>`*(p, b: untyped): untyped = macro `->`*(p, b: untyped): untyped = ## Syntax sugar for procedure types. It also supports pragmas. + ## + ## .. warning:: Semicolons can not be used to separate procedure arguments. runnableExamples: proc passTwoAndTwo(f: (int, int) -> int): int = f(2, 2) # is the same as: @@ -186,7 +190,7 @@ macro dumpToString*(x: untyped): string = assert dumpToString(a + x) == "a + x: 1 + x = 11" template square(x): untyped = x * x assert dumpToString(square(x)) == "square(x): x * x = 100" - assert not compiles dumpToString(1 + nonexistant) + assert not compiles dumpToString(1 + nonexistent) import std/strutils assert "failedAssertImpl" in dumpToString(assert true) # example with a statement result = newCall(bindSym"dumpToStringImpl") @@ -199,7 +203,7 @@ proc freshIdentNodes(ast: NimNode): NimNode = # see also https://github.com/nim-lang/Nim/pull/8531#issuecomment-410436458 proc inspect(node: NimNode): NimNode = case node.kind: - of nnkIdent, nnkSym: + of nnkIdent, nnkSym, nnkOpenSymChoice, nnkClosedSymChoice, nnkOpenSym: result = ident($node) of nnkEmpty, nnkLiterals: result = node @@ -227,9 +231,19 @@ macro capture*(locals: varargs[typed], body: untyped): untyped {.since: (1, 1).} let locals = if locals.len == 1 and locals[0].kind == nnkBracket: locals[0] else: locals for arg in locals: - if arg.strVal == "result": - error("The variable name cannot be `result`!", arg) - params.add(newIdentDefs(ident(arg.strVal), freshIdentNodes getTypeInst arg)) + proc getIdent(n: NimNode): NimNode = + case n.kind + of nnkIdent, nnkSym: + let nStr = n.strVal + if nStr == "result": + error("The variable name cannot be `result`!", n) + result = ident(nStr) + of nnkHiddenDeref: result = n[0].getIdent() + else: + error("The argument to be captured `" & n.repr & "` is not a pure identifier. " & + "It is an unsupported `" & $n.kind & "` node.", n) + let argName = getIdent(arg) + params.add(newIdentDefs(argName, freshIdentNodes getTypeInst arg)) result = newNimNode(nnkCall) result.add(newProc(newEmptyNode(), params, body, nnkLambda)) for arg in locals: result.add(arg) @@ -331,9 +345,10 @@ proc collectImpl(init, body: NimNode): NimNode {.since: (1, 1).} = let res = genSym(nskVar, "collectResult") var bracketExpr: NimNode if init != nil: - expectKind init, {nnkCall, nnkIdent, nnkSym} + expectKind init, {nnkCall, nnkIdent, nnkSym, nnkClosedSymChoice, nnkOpenSymChoice, nnkOpenSym} bracketExpr = newTree(nnkBracketExpr, - if init.kind == nnkCall: freshIdentNodes(init[0]) else: freshIdentNodes(init)) + if init.kind in {nnkCall, nnkClosedSymChoice, nnkOpenSymChoice, nnkOpenSym}: + freshIdentNodes(init[0]) else: freshIdentNodes(init)) else: bracketExpr = newTree(nnkBracketExpr) let (resBody, keyType, valueType) = trans(body, res, bracketExpr) @@ -387,6 +402,10 @@ macro collect*(init, body: untyped): untyped {.since: (1, 1).} = macro collect*(body: untyped): untyped {.since: (1, 5).} = ## Same as `collect` but without an `init` parameter. + ## + ## **See also:** + ## * `sequtils.toSeq proc<sequtils.html#toSeq.t%2Cuntyped>`_ + ## * `sequtils.mapIt template<sequtils.html#mapIt.t%2Ctyped%2Cuntyped>`_ runnableExamples: import std/[sets, tables] let data = @["bird", "word"] @@ -407,10 +426,4 @@ macro collect*(body: untyped): untyped {.since: (1, 5).} = for i, d in data.pairs: {i: d} assert m == {0: "bird", 1: "word"}.toTable - # avoid `collect` when `sequtils.toSeq` suffices: - assert collect(for i in 1..3: i*i) == @[1, 4, 9] # ok in this case - assert collect(for i in 1..3: i) == @[1, 2, 3] # overkill in this case - from std/sequtils import toSeq - assert toSeq(1..3) == @[1, 2, 3] # simpler - result = collectImpl(nil, body) |