diff options
Diffstat (limited to 'compiler/sigmatch.nim')
| -rw-r--r-- | compiler/sigmatch.nim | 169 |
1 files changed, 108 insertions, 61 deletions
diff --git a/compiler/sigmatch.nim b/compiler/sigmatch.nim index f9200ea0c..f8e3459df 100644 --- a/compiler/sigmatch.nim +++ b/compiler/sigmatch.nim @@ -51,6 +51,8 @@ type isSubtype, isSubrange, # subrange of the wanted type; no type conversion # but apart from that counts as ``isSubtype`` + isInferred, # generic proc was matched against a concrete type + isInferredConvertible, # same as above, but requiring proc CC conversion isGeneric, isFromIntLit, # conversion *from* int literal; proven safe isEqual @@ -105,6 +107,7 @@ proc initCandidate*(ctx: PContext, c: var TCandidate, callee: PSym, var bound = binding[i].typ if bound != nil and formalTypeParam.kind != tyTypeDesc: bound = bound.skipTypes({tyTypeDesc}) + assert bound != nil put(c.bindings, formalTypeParam, bound) proc newCandidate*(ctx: PContext, callee: PSym, @@ -337,34 +340,60 @@ proc recordRel(c: var TCandidate, f, a: PType): TTypeRelation = proc allowsNil(f: PType): TTypeRelation {.inline.} = result = if tfNotNil notin f.flags: isSubtype else: isNone -proc procTypeRel(c: var TCandidate, f, a: PType): TTypeRelation = - proc inconsistentVarTypes(f, a: PType): bool {.inline.} = - result = f.kind != a.kind and (f.kind == tyVar or a.kind == tyVar) +proc inconsistentVarTypes(f, a: PType): bool {.inline.} = + result = f.kind != a.kind and (f.kind == tyVar or a.kind == tyVar) + +proc procParamTypeRel(c: var TCandidate, f, a: PType): TTypeRelation = + var f = f + + if a.isMetaType: + if f.isMetaType: + # We are matching a generic proc (as proc param) + # to another generic type appearing in the proc + # signature. There is a change that the target + # type is already fully-determined, so we are + # going to try resolve it + f = generateTypeInstance(c.c, c.bindings, c.call.info, f) + if f == nil or f.isMetaType: + # no luck resolving the type, so the inference fails + return isNone + let reverseRel = typeRel(c, a, f) + if reverseRel == isGeneric: + result = isInferred + inc c.genericMatches + else: + result = typeRel(c, f, a) + if result <= isSubtype or inconsistentVarTypes(f, a): + result = isNone + + if result == isEqual: + inc c.exactMatches + +proc procTypeRel(c: var TCandidate, f, a: PType): TTypeRelation = case a.kind of tyProc: if sonsLen(f) != sonsLen(a): return - # Note: We have to do unification for the parameters before the - # return type! result = isEqual # start with maximum; also correct for no # params at all - for i in countup(1, sonsLen(f)-1): - var m = typeRel(c, f.sons[i], a.sons[i]) - if m <= isSubtype or inconsistentVarTypes(f.sons[i], a.sons[i]): - return isNone - else: result = minRel(m, result) + + template checkParam(f, a) = + result = minRel(result, procParamTypeRel(c, f, a)) + if result == isNone: return + + # Note: We have to do unification for the parameters before the + # return type! + for i in 1 .. <f.sonsLen: + checkParam(f.sons[i], a.sons[i]) + if f.sons[0] != nil: if a.sons[0] != nil: - var m = typeRel(c, f.sons[0], a.sons[0]) - # Subtype is sufficient for return types! - if m < isSubtype or inconsistentVarTypes(f.sons[0], a.sons[0]): - return isNone - elif m == isSubtype: result = isConvertible - else: result = minRel(m, result) + checkParam(f.sons[0], a.sons[0]) else: return isNone elif a.sons[0] != nil: return isNone + if tfNoSideEffect in f.flags and tfNoSideEffect notin a.flags: return isNone elif tfThread in f.flags and a.flags * {tfThread, tfNoSideEffect} == {}: @@ -375,7 +404,8 @@ proc procTypeRel(c: var TCandidate, f, a: PType): TTypeRelation = elif f.callConv != a.callConv: # valid to pass a 'nimcall' thingie to 'closure': if f.callConv == ccClosure and a.callConv == ccDefault: - result = isConvertible + result = if result != isInferred: isConvertible + else: isInferredConvertible else: return isNone when useEffectSystem: @@ -401,18 +431,8 @@ proc typeRangeRel(f, a: PType): TTypeRelation {.noinline.} = proc matchUserTypeClass*(c: PContext, m: var TCandidate, ff, a: PType): TTypeRelation = - #if f.n == nil: - # let r = typeRel(m, f, a) - # return if r == isGeneric: arg else: nil - var body = ff.skipTypes({tyUserTypeClassInst}) - # var prev = PType(idTableGet(m.bindings, f)) - # if prev != nil: - # if sameType(prev, a): return arg - # else: return nil - - # pushInfoContext(arg.info) openScope(c) inc c.inTypeClass @@ -461,7 +481,6 @@ proc matchUserTypeClass*(c: PContext, m: var TCandidate, else: discard return isGeneric - # put(m.bindings, f, a) proc typeRel(c: var TCandidate, f, aOrig: PType, doBind = true): TTypeRelation = # typeRel can be used to establish various relationships between types: @@ -851,7 +870,7 @@ proc typeRel(c: var TCandidate, f, aOrig: PType, doBind = true): TTypeRelation = else: internalAssert a.sons != nil and a.sons.len > 0 c.typedescMatched = true - result = typeRel(c, f.sons[0], a.sons[0]) + result = typeRel(c, f.base, a.base) else: result = isNone else: @@ -883,20 +902,25 @@ proc typeRel(c: var TCandidate, f, aOrig: PType, doBind = true): TTypeRelation = of tyTypeDesc: var prev = PType(idTableGet(c.bindings, f)) if prev == nil: - if a.kind == tyTypeDesc: - if f.sons[0].kind == tyNone: - result = isGeneric - else: - result = typeRel(c, f.sons[0], a.sons[0]) - if result != isNone: - put(c.bindings, f, a) + # proc foo(T: typedesc, x: T) + # when `f` is an unresolved typedesc, `a` could be any + # type, so we should not perform this check earlier + if a.kind != tyTypeDesc: return isNone + + if f.base.kind == tyNone: + result = isGeneric else: - result = isNone + result = typeRel(c, f.base, a.base) + + if result != isNone: + put(c.bindings, f, a) else: - internalAssert prev.sonsLen == 1 - let toMatch = if tfUnresolved in f.flags: a - else: a.sons[0] - result = typeRel(c, prev.sons[0], toMatch) + if tfUnresolved in f.flags: + result = typeRel(c, prev.base, a) + elif a.kind == tyTypeDesc: + result = typeRel(c, prev.base, a.base) + else: + result = isNone of tyStmt: result = isGeneric @@ -987,7 +1011,7 @@ proc paramTypesMatchAux(m: var TCandidate, f, argType: PType, arg = argSemantized argType = argType c = m.c - + if tfHasStatic in fMaybeStatic.flags: # XXX: When implicit statics are the default # this will be done earlier - we just have to @@ -1000,11 +1024,33 @@ proc paramTypesMatchAux(m: var TCandidate, f, argType: PType, argType = arg.typ var - a = if c.inTypeClass > 0: argType.skipTypes({tyTypeDesc}) + a = if c.inTypeClass > 0: argType.skipTypes({tyTypeDesc, tyFieldAccessor}) else: argType r = typeRel(m, f, a) + if r != isNone and m.calleeSym != nil and + m.calleeSym.kind in {skMacro, skTemplate}: + # XXX: duplicating this is ugly, maybe we should move this + # directly into typeRel using return-like templates + case r + of isConvertible, isIntConv: inc(m.convMatches) + of isSubtype, isSubrange: inc(m.subtypeMatches) + of isGeneric, isInferred: inc(m.genericMatches) + of isInferredConvertible: inc(m.genericMatches); inc(m.convMatches) + of isFromIntLit: inc(m.intConvMatches, 256) + of isEqual: inc(m.exactMatches) + of isNone: discard + + if f.kind == tyStmt and argOrig.kind == nkDo: + return argOrig[bodyPos] + elif f.kind == tyTypeDesc: + return arg + elif f.kind == tyStatic: + return arg.typ.n + else: + return argOrig + case r of isConvertible: inc(m.convMatches) @@ -1021,24 +1067,24 @@ proc paramTypesMatchAux(m: var TCandidate, f, argType: PType, inc(m.subtypeMatches) #result = copyTree(arg) result = implicitConv(nkHiddenStdConv, f, copyTree(arg), m, c) - of isGeneric: + of isInferred, isInferredConvertible: inc(m.genericMatches) - if m.calleeSym != nil and m.calleeSym.kind in {skMacro, skTemplate}: - if f.kind == tyStmt and argOrig.kind == nkDo: - result = argOrig[bodyPos] - elif f.kind == tyTypeDesc: - result = arg - elif f.kind == tyStatic: - result = arg.typ.n - else: - result = argOrig + if arg.kind in {nkProcDef, nkIteratorDef} + nkLambdaKinds: + result = c.semInferredLambda(c, m.bindings, arg) else: - result = copyTree(arg) - result.typ = getInstantiatedType(c, arg, m, f) - # BUG: f may not be the right key! - if skipTypes(result.typ, abstractVar-{tyTypeDesc}).kind in {tyTuple}: - result = implicitConv(nkHiddenStdConv, f, copyTree(arg), m, c) - # BUGFIX: use ``result.typ`` and not `f` here + let inferred = c.semGenerateInstance(c, arg.sym, m.bindings, arg.info) + result = newSymNode(inferred, arg.info) + if r == isInferredConvertible: + inc(m.convMatches) + result = implicitConv(nkHiddenStdConv, f, result, m, c) + of isGeneric: + inc(m.genericMatches) + result = copyTree(arg) + result.typ = getInstantiatedType(c, arg, m, f) + # BUG: f may not be the right key! + if skipTypes(result.typ, abstractVar-{tyTypeDesc}).kind in {tyTuple}: + result = implicitConv(nkHiddenStdConv, f, copyTree(arg), m, c) + # BUGFIX: use ``result.typ`` and not `f` here of isFromIntLit: # too lazy to introduce another ``*matches`` field, so we conflate # ``isIntConv`` and ``isIntLit`` here: @@ -1081,6 +1127,7 @@ proc paramTypesMatch*(m: var TCandidate, f, a: PType, # incorrect to simply use the first fitting match. However, to implement # this correctly is inefficient. We have to copy `m` here to be able to # roll back the side effects of the unification algorithm. + let c = m.c var x, y, z: TCandidate initCandidate(c, x, m.callee) @@ -1102,10 +1149,10 @@ proc paramTypesMatch*(m: var TCandidate, f, a: PType, x.state = csMatch of csMatch: var cmp = cmpCandidates(x, z) - if cmp < 0: + if cmp < 0: best = i x = z - elif cmp == 0: + elif cmp == 0: y = z # z is as good as x if x.state == csEmpty: result = nil |