diff options
Diffstat (limited to 'compiler/patterns.nim')
| -rw-r--r-- | compiler/patterns.nim | 54 |
1 files changed, 43 insertions, 11 deletions
diff --git a/compiler/patterns.nim b/compiler/patterns.nim index 1ef903161..32ec7fb53 100644 --- a/compiler/patterns.nim +++ b/compiler/patterns.nim @@ -13,6 +13,9 @@ import ast, types, semdata, sigmatch, idents, aliases, parampatterns, trees +when defined(nimPreviewSlimSystem): + import std/assertions + type TPatternContext = object owner: PSym @@ -26,6 +29,8 @@ type proc getLazy(c: PPatternContext, sym: PSym): PNode = if c.mappingIsFull: result = c.mapping[sym.position] + else: + result = nil proc putLazy(c: PPatternContext, sym: PSym, n: PNode) = if not c.mappingIsFull: @@ -36,12 +41,12 @@ proc putLazy(c: PPatternContext, sym: PSym, n: PNode) = proc matches(c: PPatternContext, p, n: PNode): bool proc canonKind(n: PNode): TNodeKind = - ## nodekind canonilization for pattern matching + ## nodekind canonicalization for pattern matching result = n.kind case result of nkCallKinds: result = nkCall of nkStrLit..nkTripleStrLit: result = nkStrLit - of nkFastAsgn: result = nkAsgn + of nkFastAsgn, nkSinkAsgn: result = nkAsgn else: discard proc sameKinds(a, b: PNode): bool {.inline.} = @@ -62,14 +67,21 @@ proc sameTrees*(a, b: PNode): bool = for i in 0..<a.len: if not sameTrees(a[i], b[i]): return result = true + else: + result = false + else: + result = false proc inSymChoice(sc, x: PNode): bool = if sc.kind == nkClosedSymChoice: + result = false for i in 0..<sc.len: if sc[i].sym == x.sym: return true elif sc.kind == nkOpenSymChoice: # same name suffices for open sym choices! result = sc[0].sym.name.id == x.sym.name.id + else: + result = false proc checkTypes(c: PPatternContext, p: PSym, n: PNode): bool = # check param constraints first here as this is quite optimized: @@ -85,6 +97,7 @@ proc isPatternParam(c: PPatternContext, p: PNode): bool {.inline.} = result = p.kind == nkSym and p.sym.kind == skParam and p.sym.owner == c.owner proc matchChoice(c: PPatternContext, p, n: PNode): bool = + result = false for i in 1..<p.len: if matches(c, p[i], n): return true @@ -96,6 +109,8 @@ proc bindOrCheck(c: PPatternContext, param: PSym, n: PNode): bool = elif n.kind == nkArgList or checkTypes(c, param, n): putLazy(c, param, n) result = true + else: + result = false proc gather(c: PPatternContext, param: PSym, n: PNode) = var pp = getLazy(c, param) @@ -129,6 +144,10 @@ proc matchNested(c: PPatternContext, p, n: PNode, rpn: bool): bool = var arglist = newNodeI(nkArgList, n.info) if matchStarAux(c, p, n, arglist, rpn): result = bindOrCheck(c, p[2].sym, arglist) + else: + result = false + else: + result = false proc matches(c: PPatternContext, p, n: PNode): bool = let n = skipHidden(n) @@ -143,7 +162,8 @@ proc matches(c: PPatternContext, p, n: PNode): bool = elif n.kind == nkSym and n.sym.kind == skConst: # try both: if p.kind == nkSym: result = p.sym == n.sym - elif matches(c, p, n.sym.ast): result = true + elif matches(c, p, n.sym.astdef): result = true + else: result = false elif p.kind == nkPattern: # pattern operators: | * let opr = p[0].ident.s @@ -152,7 +172,9 @@ proc matches(c: PPatternContext, p, n: PNode): bool = of "*": result = matchNested(c, p, n, rpn=false) of "**": result = matchNested(c, p, n, rpn=true) of "~": result = not matches(c, p[1], n) - else: doAssert(false, "invalid pattern") + else: + result = false + doAssert(false, "invalid pattern") # template {add(a, `&` * b)}(a: string{noalias}, b: varargs[string]) = # a.add(b) elif p.kind == nkCurlyExpr: @@ -160,10 +182,14 @@ proc matches(c: PPatternContext, p, n: PNode): bool = if matches(c, p[0], n): gather(c, p[1][1].sym, n) result = true + else: + result = false else: assert isPatternParam(c, p[1]) if matches(c, p[0], n): result = bindOrCheck(c, p[1].sym, n) + else: + result = false elif sameKinds(p, n): case p.kind of nkSym: result = p.sym == n.sym @@ -176,6 +202,7 @@ proc matches(c: PPatternContext, p, n: PNode): bool = else: # special rule for p(X) ~ f(...); this also works for stuff like # partial case statements, etc! - Not really ... :-/ + result = false let v = lastSon(p) if isPatternParam(c, v) and v.sym.typ.kind == tyVarargs: var arglist: PNode @@ -204,6 +231,8 @@ proc matches(c: PPatternContext, p, n: PNode): bool = for i in 0..<p.len: if not matches(c, p[i], n[i]): return result = true + else: + result = false proc matchStmtList(c: PPatternContext, p, n: PNode): PNode = proc matchRange(c: PPatternContext, p, n: PNode, i: int): bool = @@ -216,6 +245,7 @@ proc matchStmtList(c: PPatternContext, p, n: PNode): PNode = result = true if p.kind == nkStmtList and n.kind == p.kind and p.len < n.len: + result = nil let n = flattenStmts(n) # no need to flatten 'p' here as that has already been done for i in 0..n.len - p.len: @@ -228,8 +258,11 @@ proc matchStmtList(c: PPatternContext, p, n: PNode): PNode = break elif matches(c, p, n): result = n + else: + result = nil proc aliasAnalysisRequested(params: PNode): bool = + result = false if params.len >= 2: for i in 1..<params.len: let param = params[i].sym @@ -243,10 +276,7 @@ proc addToArgList(result, n: PNode) = proc applyRule*(c: PContext, s: PSym, n: PNode): PNode = ## returns a tree to semcheck if the rule triggered; nil otherwise - var ctx: TPatternContext - ctx.owner = s - ctx.c = c - ctx.formals = s.typ.len-1 + var ctx = TPatternContext(owner: s, c: c, formals: s.typ.paramsLen) var m = matchStmtList(ctx, s.ast[patternPos], n) if isNil(m): return nil # each parameter should have been bound; we simply setup a call and @@ -255,9 +285,11 @@ proc applyRule*(c: PContext, s: PSym, n: PNode): PNode = result.add(newSymNode(s, n.info)) let params = s.typ.n let requiresAA = aliasAnalysisRequested(params) - var args: PNode - if requiresAA: - args = newNodeI(nkArgList, n.info) + var args: PNode = + if requiresAA: + newNodeI(nkArgList, n.info) + else: + nil for i in 1..<params.len: let param = params[i].sym let x = getLazy(ctx, param) |