! Copyright (C) 2008 Chris Double. ! See http://factorcode.org/license.txt for BSD license. USING: kernel accessors peg peg.ebnf peg.javascript.ast peg.javascript.tokenizer ; IN: peg.javascript.parser #! Grammar for JavaScript. Based on OMeta-JS example from: #! http://jarrett.cs.ucla.edu/ometa-js/#JavaScript_Compiler #! The interesting thing about this parser is the mixing of #! a default and non-default tokenizer. The JavaScript tokenizer #! removes all newlines. So when operating on tokens there is no #! need for newline and space skipping in the grammar. But JavaScript #! uses the newline in the 'automatic semicolon insertion' rule. #! #! If a statement ends in a newline, sometimes the semicolon can be #! skipped. So we define an 'nl' rule using the default tokenizer. #! This operates a character at a time. Using this 'nl' in the parser #! allows us to detect newlines when we need to for the semicolon #! insertion rule, but ignore it in all other places. EBNF: javascript tokenizer = default nl = "\r" "\n" | "\n" tokenizer = End = !(.) Space = " " | "\t" | "\n" Spaces = Space* => [[ ignore ]] Name = . ?[ ast-name? ]? => [[ value>> ]] Number = . ?[ ast-number? ]? String = . ?[ ast-string? ]? RegExp = . ?[ ast-regexp? ]? SpacesNoNl = (!(nl) Space)* => [[ ignore ]] Expr = OrExpr:e "?" Expr:t ":" Expr:f => [[ e t f ast-cond-expr boa ]] | OrExpr:e "=" Expr:rhs => [[ e rhs ast-set boa ]] | OrExpr:e "+=" Expr:rhs => [[ e rhs "+" ast-mset boa ]] | OrExpr:e "-=" Expr:rhs => [[ e rhs "-" ast-mset boa ]] | OrExpr:e "*=" Expr:rhs => [[ e rhs "*" ast-mset boa ]] | OrExpr:e "/=" Expr:rhs => [[ e rhs "/" ast-mset boa ]] | OrExpr:e "%=" Expr:rhs => [[ e rhs "%" ast-mset boa ]] | OrExpr:e "&&=" Expr:rhs => [[ e rhs "&&" ast-mset boa ]] | OrExpr:e "||=" Expr:rhs => [[ e rhs "||" ast-mset boa ]] | OrExpr:e "^=" Expr:rhs => [[ e rhs "^" ast-mset boa ]] | OrExpr:e "&=" Expr:rhs => [[ e rhs "&" ast-mset boa ]] | OrExpr:e "|=" Expr:rhs => [[ e rhs "|" ast-mset boa ]] | OrExpr:e "<<=" Expr:rhs => [[ e rhs "<<" ast-mset boa ]] | OrExpr:e ">>=" Expr:rhs => [[ e rhs ">>" ast-mset boa ]] | OrExpr:e ">>>=" Expr:rhs => [[ e rhs ">>>" ast-mset boa ]] | OrExpr:e => [[ e ]] ExprNoIn = OrExprNoIn:e "?" ExprNoIn:t ":" ExprNoIn:f => [[ e t f ast-cond-expr boa ]] | OrExprNoIn:e "=" ExprNoIn:rhs => [[ e rhs ast-set boa ]] | OrExprNoIn:e "+=" ExprNoIn:rhs => [[ e rhs "+" ast-mset boa ]] | OrExprNoIn:e "-=" ExprNoIn:rhs => [[ e rhs "-" ast-mset boa ]] | OrExprNoIn:e "*=" ExprNoIn:rhs => [[ e rhs "*" ast-mset boa ]] | OrExprNoIn:e "/=" ExprNoIn:rhs => [[ e rhs "/" ast-mset boa ]] | OrExprNoIn:e "%=" ExprNoIn:rhs => [[ e rhs "%" ast-mset boa ]] | OrExprNoIn:e "&&=" ExprNoIn:rhs => [[ e rhs "&&" ast-mset boa ]] | OrExprNoIn:e "||=" ExprNoIn:rhs => [[ e rhs "||" ast-mset boa ]] | OrExprNoIn:e "^=" ExprNoIn:rhs => [[ e rhs "^" ast-mset boa ]] | OrExprNoIn:e "&=" ExprNoIn:rhs => [[ e rhs "&" ast-mset boa ]] | OrExprNoIn:e "|=" ExprNoIn:rhs => [[ e rhs "|" ast-mset boa ]] | OrExprNoIn:e "<<=" ExprNoIn:rhs => [[ e rhs "<<" ast-mset boa ]] | OrExprNoIn:e ">>=" ExprNoIn:rhs => [[ e rhs ">>" ast-mset boa ]] | OrExprNoIn:e ">>>=" ExprNoIn:rhs => [[ e rhs ">>>" ast-mset boa ]] | OrExprNoIn:e => [[ e ]] OrExpr = OrExpr:x "||" AndExpr:y => [[ x y "||" ast-binop boa ]] | AndExpr OrExprNoIn = OrExprNoIn:x "||" AndExprNoIn:y => [[ x y "||" ast-binop boa ]] | AndExprNoIn AndExpr = AndExpr:x "&&" BitOrExpr:y => [[ x y "&&" ast-binop boa ]] | BitOrExpr AndExprNoIn = AndExprNoIn:x "&&" BitOrExprNoIn:y => [[ x y "&&" ast-binop boa ]] | BitOrExprNoIn BitOrExpr = BitOrExpr:x "|" BitXORExpr:y => [[ x y "|" ast-binop boa ]] | BitXORExpr BitOrExprNoIn = BitOrExprNoIn:x "|" BitXORExprNoIn:y => [[ x y "|" ast-binop boa ]] | BitXORExprNoIn BitXORExpr = BitXORExpr:x "^" BitANDExpr:y => [[ x y "^" ast-binop boa ]] | BitANDExpr BitXORExprNoIn = BitXORExprNoIn:x "^" BitANDExprNoIn:y => [[ x y "^" ast-binop boa ]] | BitANDExprNoIn BitANDExpr = BitANDExpr:x "&" EqExpr:y => [[ x y "&" ast-binop boa ]] | EqExpr BitANDExprNoIn = BitANDExprNoIn:x "&" EqExprNoIn:y => [[ x y "&" ast-binop boa ]] | EqExprNoIn EqExpr = EqExpr:x "==" RelExpr:y => [[ x y "==" ast-binop boa ]] | EqExpr:x "!=" RelExpr:y => [[ x y "!=" ast-binop boa ]] | EqExpr:x "===" RelExpr:y => [[ x y "===" ast-binop boa ]] | EqExpr:x "!==" RelExpr:y => [[ x y "!==" ast-binop boa ]] | RelExpr EqExprNoIn = EqExprNoIn:x "==" RelExprNoIn:y => [[ x y "==" ast-binop boa ]] | EqExprNoIn:x "!=" RelExprNoIn:y => [[ x y "!=" ast-binop boa ]] | EqExprNoIn:x "===" RelExprNoIn:y => [[ x y "===" ast-binop boa ]] | EqExprNoIn:x "!==" RelExprNoIn:y => [[ x y "!==" ast-binop boa ]] | RelExprNoIn RelExpr = RelExpr:x ">" ShiftExpr:y => [[ x y ">" ast-binop boa ]] | RelExpr:x ">=" ShiftExpr:y => [[ x y ">=" ast-binop boa ]] | RelExpr:x "<" ShiftExpr:y => [[ x y "<" ast-binop boa ]] | RelExpr:x "<=" ShiftExpr:y => [[ x y "<=" ast-binop boa ]] | RelExpr:x "instanceof" ShiftExpr:y => [[ x y "instanceof" ast-binop boa ]] | RelExpr:x "in" ShiftExpr:y => [[ x y "in" ast-binop boa ]] | ShiftExpr RelExprNoIn = RelExprNoIn:x ">" ShiftExpr:y => [[ x y ">" ast-binop boa ]] | RelExprNoIn:x ">=" ShiftExpr:y => [[ x y ">=" ast-binop boa ]] | RelExprNoIn:x "<" ShiftExpr:y => [[ x y "<" ast-binop boa ]] | RelExprNoIn:x "<=" ShiftExpr:y => [[ x y "<=" ast-binop boa ]] | RelExprNoIn:x "instanceof" ShiftExpr:y => [[ x y "instanceof" ast-binop boa ]] | ShiftExpr ShiftExpr = ShiftExpr:x "<<" AddExpr:y => [[ x y "<<" ast-binop boa ]] | ShiftExpr:x ">>>" AddExpr:y => [[ x y ">>>" ast-binop boa ]] | ShiftExpr:x ">>" AddExpr:y => [[ x y ">>" ast-binop boa ]] | AddExpr AddExpr = AddExpr:x "+" MulExpr:y => [[ x y "+" ast-binop boa ]] | AddExpr:x "-" MulExpr:y => [[ x y "-" ast-binop boa ]] | MulExpr MulExpr = MulExpr:x "*" Unary:y => [[ x y "*" ast-binop boa ]] | MulExpr:x "/" Unary:y => [[ x y "/" ast-binop boa ]] | MulExpr:x "%" Unary:y => [[ x y "%" ast-binop boa ]] | Unary Unary = "-" Unary:p => [[ p "-" ast-unop boa ]] | "+" Unary:p => [[ p ]] | "++" Unary:p => [[ p "++" ast-preop boa ]] | "--" Unary:p => [[ p "--" ast-preop boa ]] | "!" Unary:p => [[ p "!" ast-unop boa ]] | "typeof" Unary:p => [[ p "typeof" ast-unop boa ]] | "void" Unary:p => [[ p "void" ast-unop boa ]] | "delete" Unary:p => [[ p "delete" ast-unop boa ]] | Postfix Postfix = PrimExpr:p SpacesNoNl "++" => [[ p "++" ast-postop boa ]] | PrimExpr:p SpacesNoNl "--" => [[ p "--" ast-postop boa ]] | PrimExpr Args = (Expr ("," Expr => [[ second ]])* => [[ first2 swap prefix ]])? PrimExpr = PrimExpr:p "[" Expr:i "]" => [[ i p ast-getp boa ]] | PrimExpr:p "." Name:m "(" Args:as ")" => [[ m p as ast-send boa ]] | PrimExpr:p "." Name:f => [[ f p ast-getp boa ]] | PrimExpr:p "(" Args:as ")" => [[ p as ast-call boa ]] | PrimExprHd PrimExprHd = "(" Expr:e ")" => [[ e ]] | "this" => [[ ast-this boa ]] | Name => [[ ast-get boa ]] | Number | String | RegExp | "function" FuncRest:fr => [[ fr ]] | "new" PrimExpr:n "(" Args:as ")" => [[ n as ast-new boa ]] | "new" PrimExpr:n => [[ n f ast-new boa ]] | "[" Args:es "]" => [[ es ast-array boa ]] | Json JsonBindings = (JsonBinding ("," JsonBinding => [[ second ]])* => [[ first2 swap prefix ]])? Json = "{" JsonBindings:bs "}" => [[ bs ast-json boa ]] JsonBinding = JsonPropName:n ":" Expr:v => [[ n v ast-binding boa ]] JsonPropName = Name | Number | String | RegExp Formal = Spaces Name Formals = (Formal ("," Formal => [[ second ]])* => [[ first2 swap prefix ]])? FuncRest = "(" Formals:fs ")" "{" SrcElems:body "}" => [[ fs body ast-func boa ]] Sc = SpacesNoNl (nl | &("}") | End)| ";" Binding = Name:n "=" Expr:v => [[ n v ast-var boa ]] | Name:n => [[ n "undefined" ast-get boa ast-var boa ]] Block = "{" SrcElems:ss "}" => [[ ss ]] Bindings = (Binding ("," Binding => [[ second ]])* => [[ first2 swap prefix ]])? For1 = "var" Bindings => [[ second ]] | ExprNoIn | Spaces => [[ "undefined" ast-get boa ]] For2 = Expr | Spaces => [[ "true" ast-get boa ]] For3 = Expr | Spaces => [[ "undefined" ast-get boa ]] ForIn1 = "var" Name:n => [[ n "undefined" ast-get boa ast-var boa ]] | PrimExprHd Switch1 = "case" Expr:c ":" SrcElems:cs => [[ c cs ast-case boa ]] | "default" ":" SrcElems:cs => [[ cs ast-default boa ]] SwitchBody = Switch1* Finally = "finally" Block:b => [[ b ]] | Spaces => [[ "undefined" ast-get boa ]] Stmt = Block | "var" Bindings:bs Sc => [[ bs ast-begin boa ]] | "if" "(" Expr:c ")" Stmt:t "else" Stmt:f => [[ c t f ast-if boa ]] | "if" "(" Expr:c ")" Stmt:t => [[ c t "undefined" ast-get boa ast-if boa ]] | "while" "(" Expr:c ")" Stmt:s => [[ c s ast-while boa ]] | "do" Stmt:s "while" "(" Expr:c ")" Sc => [[ s c ast-do-while boa ]] | "for" "(" For1:i ";" For2:c ";" For3:u ")" Stmt:s => [[ i c u s ast-for boa ]] | "for" "(" ForIn1:v "in" Expr:e ")" Stmt:s => [[ v e s ast-for-in boa ]] | "switch" "(" Expr:e ")" "{" SwitchBody:cs "}" => [[ e cs ast-switch boa ]] | "break" Sc => [[ ast-break boa ]] | "continue" Sc => [[ ast-continue boa ]] | "throw" SpacesNoNl Expr:e Sc => [[ e ast-throw boa ]] | "try" Block:t "catch" "(" Name:e ")" Block:c Finally:f => [[ t e c f ast-try boa ]] | "return" Expr:e Sc => [[ e ast-return boa ]] | "return" Sc => [[ "undefined" ast-get boa ast-return boa ]] | "with" "(" Expr:e ")" Stmt:b => [[ e b ast-with boa ]] | Expr:e Sc => [[ e ]] | ";" => [[ "undefined" ast-get boa ]] SrcElem = "function" Name:n FuncRest:f => [[ n f ast-var boa ]] | Stmt SrcElems = SrcElem* => [[ ast-begin boa ]] TopLevel = SrcElems Spaces ;EBNF