diff options
Diffstat (limited to 'compiler/parser.nim')
| -rw-r--r-- | compiler/parser.nim | 65 |
1 files changed, 45 insertions, 20 deletions
diff --git a/compiler/parser.nim b/compiler/parser.nim index 5a5bfb574..cfba89f4a 100644 --- a/compiler/parser.nim +++ b/compiler/parser.nim @@ -38,7 +38,6 @@ type inSemiStmtList: int proc parseAll*(p: var TParser): PNode -proc openParser*(p: var TParser, filename: string, inputstream: PLLStream) proc closeParser*(p: var TParser) proc parseTopLevelStmt*(p: var TParser): PNode # implements an iterator. Returns the next top-level statement or @@ -50,7 +49,6 @@ proc parseString*(s: string, filename: string = "", line: int = 0): PNode # correct error messages referring to the original source. # helpers for the other parsers -proc getPrecedence*(tok: TToken): int proc isOperator*(tok: TToken): bool proc getTok*(p: var TParser) proc parMessage*(p: TParser, msg: TMsgKind, arg: string = "") @@ -77,14 +75,17 @@ proc parseCase(p: var TParser): PNode proc getTok(p: var TParser) = rawGetTok(p.lex, p.tok) -proc openParser*(p: var TParser, fileIdx: int32, inputStream: PLLStream) = +proc openParser*(p: var TParser, fileIdx: int32, inputStream: PLLStream, + strongSpaces=false) = initToken(p.tok) openLexer(p.lex, fileIdx, inputStream) getTok(p) # read the first token p.firstTok = true + p.strongSpaces = strongSpaces -proc openParser*(p: var TParser, filename: string, inputStream: PLLStream) = - openParser(p, filename.fileInfoIdx, inputstream) +proc openParser*(p: var TParser, filename: string, inputStream: PLLStream, + strongSpaces=false) = + openParser(p, filename.fileInfoIdx, inputstream, strongSpaces) proc closeParser(p: var TParser) = closeLexer(p.lex) @@ -193,34 +194,52 @@ proc isSigilLike(tok: TToken): bool {.inline.} = proc isLeftAssociative(tok: TToken): bool {.inline.} = result = tok.tokType != tkOpr or relevantOprChar(tok.ident) != '^' -proc getPrecedence(tok: TToken): int = +proc getPrecedence(tok: TToken, strongSpaces: bool): int = + template considerStrongSpaces(x): expr = + x + (if strongSpaces: 100 - tok.strongSpaceA.int*10 else: 0) + case tok.tokType of tkOpr: let L = tok.ident.s.len let relevantChar = relevantOprChar(tok.ident) - template considerAsgn(value: expr) = - result = if tok.ident.s[L-1] == '=': 1 else: value + template considerAsgn(value: expr) = + result = if tok.ident.s[L-1] == '=': 1 else: considerStrongSpaces(value) case relevantChar of '$', '^': considerAsgn(10) of '*', '%', '/', '\\': considerAsgn(9) - of '~': result = 8 + of '~': result = considerStrongSpaces(8) of '+', '-', '|': considerAsgn(8) of '&': considerAsgn(7) - of '=', '<', '>', '!': result = 5 + of '=', '<', '>', '!': result = considerStrongSpaces(5) of '.': considerAsgn(6) - of '?': result = 2 + of '?': result = considerStrongSpaces(2) else: considerAsgn(2) of tkDiv, tkMod, tkShl, tkShr: result = 9 of tkIn, tkNotin, tkIs, tkIsnot, tkNot, tkOf, tkAs: result = 5 - of tkDotDot: result = 6 + of tkDotDot: result = considerStrongSpaces(6) of tkAnd: result = 4 of tkOr, tkXor: result = 3 - else: result = - 10 - -proc isOperator(tok: TToken): bool = - result = getPrecedence(tok) >= 0 + else: result = -10 + +proc isOperator(tok: TToken): bool = + tok.tokType in {tkOpr, tkDiv, tkMod, tkShl, tkShr, tkIn, tkNotin, tkIs, + tkIsnot, tkNot, tkOf, tkAs, tkDotDot, tkAnd, tkOr, tkXor} + +proc isUnary(p: TParser): bool = + p.strongSpaces and p.tok.tokType in {tkOpr, tkDotDot} and + p.tok.strongSpaceB == 0 and + p.tok.strongSpaceA > 0 + +proc checkBinary(p: TParser) {.inline.} = + # we don't check '..' here as that's too annoying + if p.strongSpaces and p.tok.tokType == tkOpr: + if p.tok.strongSpaceB > 0 and p.tok.strongSpaceA != p.tok.strongSpaceB: + parMessage(p, errGenerated, "number of spaces around '$#' not consistent"% + prettyTok(p.tok)) + elif p.tok.strongSpaceA notin {0,1,2,4,8}: + parMessage(p, errGenerated, "number of spaces must be 0,1,2,4 or 8") #| module = stmt ^* (';' / IND{=}) #| @@ -650,6 +669,7 @@ proc primarySuffix(p: var TParser, r: PNode): PNode = while p.tok.indent < 0: case p.tok.tokType of tkParLe: + if p.strongSpaces and p.tok.strongSpaceA > 0: break result = namedParams(p, result, nkCall, tkParRi) if result.len > 1 and result.sons[1].kind == nkExprColonExpr: result.kind = nkObjConstr @@ -664,8 +684,10 @@ proc primarySuffix(p: var TParser, r: PNode): PNode = result = dotExpr(p, result) result = parseGStrLit(p, result) of tkBracketLe: + if p.strongSpaces and p.tok.strongSpaceA > 0: break result = namedParams(p, result, nkBracketExpr, tkBracketRi) of tkCurlyLe: + if p.strongSpaces and p.tok.strongSpaceA > 0: break result = namedParams(p, result, nkCurlyExpr, tkCurlyRi) of tkSymbol, tkAccent, tkIntLit..tkCharLit, tkNil, tkCast: if p.inPragma == 0: @@ -695,10 +717,11 @@ proc primary(p: var TParser, mode: TPrimaryMode): PNode proc simpleExprAux(p: var TParser, limit: int, mode: TPrimaryMode): PNode = result = primary(p, mode) # expand while operators have priorities higher than 'limit' - var opPrec = getPrecedence(p.tok) + var opPrec = getPrecedence(p.tok, p.strongSpaces) let modeB = if mode == pmTypeDef: pmTypeDesc else: mode # the operator itself must not start on a new line: - while opPrec >= limit and p.tok.indent < 0: + while opPrec >= limit and p.tok.indent < 0 and not isUnary(p): + checkBinary(p) var leftAssoc = ord(isLeftAssociative(p.tok)) var a = newNodeP(nkInfix, p) var opNode = newIdentNodeP(p.tok.ident, p) # skip operator: @@ -710,7 +733,7 @@ proc simpleExprAux(p: var TParser, limit: int, mode: TPrimaryMode): PNode = addSon(a, result) addSon(a, b) result = a - opPrec = getPrecedence(p.tok) + opPrec = getPrecedence(p.tok, p.strongSpaces) proc simpleExpr(p: var TParser, mode = pmNormal): PNode = result = simpleExprAux(p, -1, mode) @@ -1933,7 +1956,9 @@ proc parseString(s: string, filename: string = "", line: int = 0): PNode = stream.lineOffset = line var parser: TParser - openParser(parser, filename, stream) + # XXX for now the builtin 'parseStmt/Expr' functions do not know about strong + # spaces... + openParser(parser, filename, stream, false) result = parser.parseAll closeParser(parser) |