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fix #1858; Add support for generic templates and macros

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Implementation notes:
Just after overload resolution, the resolved generic params will be added to the
call expression to be later processed in evalTemplate and evalMacroCall. These
procs have been modified to handle the increased number of parameters, but one
remaining issue is that immediate templates and macros don't go through the same
process. The next commit will outlaw the use of generic parameters with such macros.
This commit is contained in:
Zahary Karadjov 2015-01-05 03:51:18 +02:00
commit 5e4ae8dbb4
6 changed files with 109 additions and 44 deletions
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52
compiler/evaltempl.nim
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@ -25,16 +25,22 @@ proc copyNode(ctx: TemplCtx, a, b: PNode): PNode =
if ctx.instLines: result.info = b.info
proc evalTemplateAux(templ, actual: PNode, c: var TemplCtx, result: PNode) =
template handleParam(param) =
let x = param
if x.kind == nkArgList:
for y in items(x): result.add(y)
else:
result.add copyTree(x)
case templ.kind
of nkSym:
var s = templ.sym
if s.owner.id == c.owner.id:
if s.kind == skParam:
let x = actual.sons[s.position]
if x.kind == nkArgList:
for y in items(x): result.add(y)
else:
result.add copyTree(x)
case s.kind
of skParam:
handleParam actual.sons[s.position]
of skGenericParam:
handleParam actual.sons[s.owner.typ.len + s.position - 1]
else:
internalAssert sfGenSym in s.flags
var x = PSym(idTableGet(c.mapping, s))
@ -56,21 +62,31 @@ proc evalTemplateAux(templ, actual: PNode, c: var TemplCtx, result: PNode) =
proc evalTemplateArgs(n: PNode, s: PSym): PNode =
# if the template has zero arguments, it can be called without ``()``
# `n` is then a nkSym or something similar
var a: int
case n.kind
of nkCall, nkInfix, nkPrefix, nkPostfix, nkCommand, nkCallStrLit:
a = sonsLen(n)
else: a = 0
var f = s.typ.sonsLen
if a > f: globalError(n.info, errWrongNumberOfArguments)
var totalParams = case n.kind
of nkCall, nkInfix, nkPrefix, nkPostfix, nkCommand, nkCallStrLit: <n.len
else: 0
var
genericParams = s.ast[genericParamsPos].len
expectedRegularParams = <s.typ.len
givenRegularParams = totalParams - genericParams
if totalParams > expectedRegularParams + genericParams:
globalError(n.info, errWrongNumberOfArguments)
result = newNodeI(nkArgList, n.info)
for i in countup(1, f - 1):
var arg = if i < a: n.sons[i] else: copyTree(s.typ.n.sons[i].sym.ast)
if arg == nil or arg.kind == nkEmpty:
localError(n.info, errWrongNumberOfArguments)
addSon(result, arg)
for i in 1 .. givenRegularParams:
result.addSon n.sons[i]
for i in givenRegularParams+1 .. expectedRegularParams:
let default = s.typ.n.sons[i].sym.ast
if default.kind == nkEmpty:
localError(n.info, errWrongNumberOfArguments)
result.addSon default.copyTree
for i in 1 .. genericParams:
result.addSon n.sons[givenRegularParams + i]
var evalTemplateCounter* = 0
# to prevent endless recursion in templates instantiation