X-Git-Url: http://git.asbjorn.biz/?p=jquery.git;a=blobdiff_plain;f=build%2Flib%2Fparse-js.js;fp=build%2Flib%2Fparse-js.js;h=7e4fd0e272d10886aa5580005ec0ffacfedc50f9;hp=0000000000000000000000000000000000000000;hb=d503845d0cf45632c0d7c3542ffd1b19257a8e5e;hpb=9c76ac4f6d295a5b593048e54b4c4231c092e58a diff --git a/build/lib/parse-js.js b/build/lib/parse-js.js new file mode 100644 index 0000000..7e4fd0e --- /dev/null +++ b/build/lib/parse-js.js @@ -0,0 +1,1239 @@ +/*********************************************************************** + + A JavaScript tokenizer / parser / beautifier / compressor. + + This version is suitable for Node.js. With minimal changes (the + exports stuff) it should work on any JS platform. + + This file contains the tokenizer/parser. It is a port to JavaScript + of parse-js [1], a JavaScript parser library written in Common Lisp + by Marijn Haverbeke. Thank you Marijn! + + [1] http://marijn.haverbeke.nl/parse-js/ + + Exported functions: + + - tokenizer(code) -- returns a function. Call the returned + function to fetch the next token. + + - parse(code) -- returns an AST of the given JavaScript code. + + -------------------------------- (C) --------------------------------- + + Author: Mihai Bazon + + http://mihai.bazon.net/blog + + Distributed under the BSD license: + + Copyright 2010 (c) Mihai Bazon + Based on parse-js (http://marijn.haverbeke.nl/parse-js/). + + Redistribution and use in source and binary forms, with or without + modification, are permitted provided that the following conditions + are met: + + * Redistributions of source code must retain the above + copyright notice, this list of conditions and the following + disclaimer. + + * Redistributions in binary form must reproduce the above + copyright notice, this list of conditions and the following + disclaimer in the documentation and/or other materials + provided with the distribution. + + THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDER “AS IS” AND ANY + EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE + IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR + PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER BE + LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, + OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, + PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR + PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY + THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR + TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF + THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF + SUCH DAMAGE. + + ***********************************************************************/ + +/* -----[ Tokenizer (constants) ]----- */ + +var KEYWORDS = array_to_hash([ + "break", + "case", + "catch", + "const", + "continue", + "default", + "delete", + "do", + "else", + "finally", + "for", + "function", + "if", + "in", + "instanceof", + "new", + "return", + "switch", + "throw", + "try", + "typeof", + "var", + "void", + "while", + "with" +]); + +var RESERVED_WORDS = array_to_hash([ + "abstract", + "boolean", + "byte", + "char", + "class", + "debugger", + "double", + "enum", + "export", + "extends", + "final", + "float", + "goto", + "implements", + "import", + "int", + "interface", + "long", + "native", + "package", + "private", + "protected", + "public", + "short", + "static", + "super", + "synchronized", + "throws", + "transient", + "volatile" +]); + +var KEYWORDS_BEFORE_EXPRESSION = array_to_hash([ + "return", + "new", + "delete", + "throw", + "else", + "case" +]); + +var KEYWORDS_ATOM = array_to_hash([ + "false", + "null", + "true", + "undefined" +]); + +var OPERATOR_CHARS = array_to_hash(characters("+-*&%=<>!?|~^")); + +var RE_HEX_NUMBER = /^0x[0-9a-f]+$/i; +var RE_OCT_NUMBER = /^0[0-7]+$/; +var RE_DEC_NUMBER = /^\d*\.?\d*(?:e[+-]?\d*(?:\d\.?|\.?\d)\d*)?$/i; + +var OPERATORS = array_to_hash([ + "in", + "instanceof", + "typeof", + "new", + "void", + "delete", + "++", + "--", + "+", + "-", + "!", + "~", + "&", + "|", + "^", + "*", + "/", + "%", + ">>", + "<<", + ">>>", + "<", + ">", + "<=", + ">=", + "==", + "===", + "!=", + "!==", + "?", + "=", + "+=", + "-=", + "/=", + "*=", + "%=", + ">>=", + "<<=", + ">>>=", + "~=", + "%=", + "|=", + "^=", + "&=", + "&&", + "||" +]); + +var WHITESPACE_CHARS = array_to_hash(characters(" \n\r\t")); + +var PUNC_BEFORE_EXPRESSION = array_to_hash(characters("[{}(,.;:")); + +var PUNC_CHARS = array_to_hash(characters("[]{}(),;:")); + +var REGEXP_MODIFIERS = array_to_hash(characters("gmsiy")); + +/* -----[ Tokenizer ]----- */ + +function is_alphanumeric_char(ch) { + ch = ch.charCodeAt(0); + return (ch >= 48 && ch <= 57) || + (ch >= 65 && ch <= 90) || + (ch >= 97 && ch <= 122); +}; + +function is_identifier_char(ch) { + return is_alphanumeric_char(ch) || ch == "$" || ch == "_"; +}; + +function is_digit(ch) { + ch = ch.charCodeAt(0); + return ch >= 48 && ch <= 57; +}; + +function parse_js_number(num) { + if (RE_HEX_NUMBER.test(num)) { + return parseInt(num.substr(2), 16); + } else if (RE_OCT_NUMBER.test(num)) { + return parseInt(num.substr(1), 8); + } else if (RE_DEC_NUMBER.test(num)) { + return parseFloat(num); + } +}; + +function JS_Parse_Error(message, line, col, pos) { + this.message = message; + this.line = line; + this.col = col; + this.pos = pos; + try { + ({})(); + } catch(ex) { + this.stack = ex.stack; + }; +}; + +JS_Parse_Error.prototype.toString = function() { + return this.message + " (line: " + this.line + ", col: " + this.col + ", pos: " + this.pos + ")" + "\n\n" + this.stack; +}; + +function js_error(message, line, col, pos) { + throw new JS_Parse_Error(message, line, col, pos); +}; + +function is_token(token, type, val) { + return token.type == type && (val == null || token.value == val); +}; + +var EX_EOF = {}; + +function tokenizer($TEXT, skip_comments) { + + var S = { + text : $TEXT.replace(/\r\n?|[\n\u2028\u2029]/g, "\n").replace(/^\uFEFF/, ''), + pos : 0, + tokpos : 0, + line : 0, + tokline : 0, + col : 0, + tokcol : 0, + newline_before : false, + regex_allowed : false + }; + + function peek() { return S.text.charAt(S.pos); }; + + function next(signal_eof) { + var ch = S.text.charAt(S.pos++); + if (signal_eof && !ch) + throw EX_EOF; + if (ch == "\n") { + S.newline_before = true; + ++S.line; + S.col = 0; + } else { + ++S.col; + } + return ch; + }; + + function eof() { + return !S.peek(); + }; + + function find(what, signal_eof) { + var pos = S.text.indexOf(what, S.pos); + if (signal_eof && pos == -1) throw EX_EOF; + return pos; + }; + + function start_token() { + S.tokline = S.line; + S.tokcol = S.col; + S.tokpos = S.pos; + }; + + function token(type, value) { + S.regex_allowed = ((type == "operator" && !HOP(UNARY_POSTFIX, value)) || + (type == "keyword" && HOP(KEYWORDS_BEFORE_EXPRESSION, value)) || + (type == "punc" && HOP(PUNC_BEFORE_EXPRESSION, value))); + var ret = { + type : type, + value : value, + line : S.tokline, + col : S.tokcol, + pos : S.tokpos, + nlb : S.newline_before + }; + S.newline_before = false; + return ret; + }; + + function skip_whitespace() { + while (HOP(WHITESPACE_CHARS, peek())) + next(); + }; + + function read_while(pred) { + var ret = "", ch = peek(), i = 0; + while (ch && pred(ch, i++)) { + ret += next(); + ch = peek(); + } + return ret; + }; + + function parse_error(err) { + js_error(err, S.tokline, S.tokcol, S.tokpos); + }; + + function read_num(prefix) { + var has_e = false, after_e = false, has_x = false, has_dot = prefix == "."; + var num = read_while(function(ch, i){ + if (ch == "x" || ch == "X") { + if (has_x) return false; + return has_x = true; + } + if (!has_x && (ch == "E" || ch == "e")) { + if (has_e) return false; + return has_e = after_e = true; + } + if (ch == "-") { + if (after_e || (i == 0 && !prefix)) return true; + return false; + } + if (ch == "+") return after_e; + after_e = false; + if (ch == ".") { + if (!has_dot) + return has_dot = true; + return false; + } + return is_alphanumeric_char(ch); + }); + if (prefix) + num = prefix + num; + var valid = parse_js_number(num); + if (!isNaN(valid)) { + return token("num", valid); + } else { + parse_error("Invalid syntax: " + num); + } + }; + + function read_escaped_char() { + var ch = next(true); + switch (ch) { + case "n" : return "\n"; + case "r" : return "\r"; + case "t" : return "\t"; + case "b" : return "\b"; + case "v" : return "\v"; + case "f" : return "\f"; + case "0" : return "\0"; + case "x" : return String.fromCharCode(hex_bytes(2)); + case "u" : return String.fromCharCode(hex_bytes(4)); + default : return ch; + } + }; + + function hex_bytes(n) { + var num = 0; + for (; n > 0; --n) { + var digit = parseInt(next(true), 16); + if (isNaN(digit)) + parse_error("Invalid hex-character pattern in string"); + num = (num << 4) | digit; + } + return num; + }; + + function read_string() { + return with_eof_error("Unterminated string constant", function(){ + var quote = next(), ret = ""; + for (;;) { + var ch = next(true); + if (ch == "\\") ch = read_escaped_char(); + else if (ch == quote) break; + ret += ch; + } + return token("string", ret); + }); + }; + + function read_line_comment() { + next(); + var i = find("\n"), ret; + if (i == -1) { + ret = S.text.substr(S.pos); + S.pos = S.text.length; + } else { + ret = S.text.substring(S.pos, i); + S.pos = i; + } + return token("comment1", ret); + }; + + function read_multiline_comment() { + next(); + return with_eof_error("Unterminated multiline comment", function(){ + var i = find("*/", true), + text = S.text.substring(S.pos, i), + tok = token("comment2", text); + S.pos = i + 2; + S.line += text.split("\n").length - 1; + S.newline_before = text.indexOf("\n") >= 0; + return tok; + }); + }; + + function read_regexp() { + return with_eof_error("Unterminated regular expression", function(){ + var prev_backslash = false, regexp = "", ch, in_class = false; + while ((ch = next(true))) if (prev_backslash) { + regexp += "\\" + ch; + prev_backslash = false; + } else if (ch == "[") { + in_class = true; + regexp += ch; + } else if (ch == "]" && in_class) { + in_class = false; + regexp += ch; + } else if (ch == "/" && !in_class) { + break; + } else if (ch == "\\") { + prev_backslash = true; + } else { + regexp += ch; + } + var mods = read_while(function(ch){ + return HOP(REGEXP_MODIFIERS, ch); + }); + return token("regexp", [ regexp, mods ]); + }); + }; + + function read_operator(prefix) { + function grow(op) { + var bigger = op + peek(); + if (HOP(OPERATORS, bigger)) { + next(); + return grow(bigger); + } else { + return op; + } + }; + return token("operator", grow(prefix || next())); + }; + + var handle_slash = skip_comments ? function() { + next(); + var regex_allowed = S.regex_allowed; + switch (peek()) { + case "/": read_line_comment(); S.regex_allowed = regex_allowed; return next_token(); + case "*": read_multiline_comment(); S.regex_allowed = regex_allowed; return next_token(); + } + return S.regex_allowed ? read_regexp() : read_operator("/"); + } : function() { + next(); + switch (peek()) { + case "/": return read_line_comment(); + case "*": return read_multiline_comment(); + } + return S.regex_allowed ? read_regexp() : read_operator("/"); + }; + + function handle_dot() { + next(); + return is_digit(peek()) + ? read_num(".") + : token("punc", "."); + }; + + function read_word() { + var word = read_while(is_identifier_char); + return !HOP(KEYWORDS, word) + ? token("name", word) + : HOP(OPERATORS, word) + ? token("operator", word) + : HOP(KEYWORDS_ATOM, word) + ? token("atom", word) + : token("keyword", word); + }; + + function with_eof_error(eof_error, cont) { + try { + return cont(); + } catch(ex) { + if (ex === EX_EOF) parse_error(eof_error); + else throw ex; + } + }; + + function next_token(force_regexp) { + if (force_regexp) + return read_regexp(); + skip_whitespace(); + start_token(); + var ch = peek(); + if (!ch) return token("eof"); + if (is_digit(ch)) return read_num(); + if (ch == '"' || ch == "'") return read_string(); + if (HOP(PUNC_CHARS, ch)) return token("punc", next()); + if (ch == ".") return handle_dot(); + if (ch == "/") return handle_slash(); + if (HOP(OPERATOR_CHARS, ch)) return read_operator(); + if (is_identifier_char(ch)) return read_word(); + parse_error("Unexpected character '" + ch + "'"); + }; + + next_token.context = function(nc) { + if (nc) S = nc; + return S; + }; + + return next_token; + +}; + +/* -----[ Parser (constants) ]----- */ + +var UNARY_PREFIX = array_to_hash([ + "typeof", + "void", + "delete", + "--", + "++", + "!", + "~", + "-", + "+" +]); + +var UNARY_POSTFIX = array_to_hash([ "--", "++" ]); + +var ASSIGNMENT = (function(a, ret, i){ + while (i < a.length) { + ret[a[i]] = a[i].substr(0, a[i].length - 1); + i++; + } + return ret; +})( + ["+=", "-=", "/=", "*=", "%=", ">>=", "<<=", ">>>=", "~=", "%=", "|=", "^=", "&="], + { "=": true }, + 0 +); + +var PRECEDENCE = (function(a, ret){ + for (var i = 0, n = 1; i < a.length; ++i, ++n) { + var b = a[i]; + for (var j = 0; j < b.length; ++j) { + ret[b[j]] = n; + } + } + return ret; +})( + [ + ["||"], + ["&&"], + ["|"], + ["^"], + ["&"], + ["==", "===", "!=", "!=="], + ["<", ">", "<=", ">=", "in", "instanceof"], + [">>", "<<", ">>>"], + ["+", "-"], + ["*", "/", "%"] + ], + {} +); + +var STATEMENTS_WITH_LABELS = array_to_hash([ "for", "do", "while", "switch" ]); + +var ATOMIC_START_TOKEN = array_to_hash([ "atom", "num", "string", "regexp", "name" ]); + +/* -----[ Parser ]----- */ + +function NodeWithToken(str, start, end) { + this.name = str; + this.start = start; + this.end = end; +}; + +NodeWithToken.prototype.toString = function() { return this.name; }; + +function parse($TEXT, strict_mode, embed_tokens) { + + var S = { + input: tokenizer($TEXT, true), + token: null, + prev: null, + peeked: null, + in_function: 0, + in_loop: 0, + labels: [] + }; + + S.token = next(); + + function is(type, value) { + return is_token(S.token, type, value); + }; + + function peek() { return S.peeked || (S.peeked = S.input()); }; + + function next() { + S.prev = S.token; + if (S.peeked) { + S.token = S.peeked; + S.peeked = null; + } else { + S.token = S.input(); + } + return S.token; + }; + + function prev() { + return S.prev; + }; + + function croak(msg, line, col, pos) { + var ctx = S.input.context(); + js_error(msg, + line != null ? line : ctx.tokline, + col != null ? col : ctx.tokcol, + pos != null ? pos : ctx.tokpos); + }; + + function token_error(token, msg) { + croak(msg, token.line, token.col); + }; + + function unexpected(token) { + if (token == null) + token = S.token; + token_error(token, "Unexpected token: " + token.type + " (" + token.value + ")"); + }; + + function expect_token(type, val) { + if (is(type, val)) { + return next(); + } + token_error(S.token, "Unexpected token " + S.token.type + ", expected " + type); + }; + + function expect(punc) { return expect_token("punc", punc); }; + + function can_insert_semicolon() { + return !strict_mode && ( + S.token.nlb || is("eof") || is("punc", "}") + ); + }; + + function semicolon() { + if (is("punc", ";")) next(); + else if (!can_insert_semicolon()) unexpected(); + }; + + function as() { + return slice(arguments); + }; + + function parenthesised() { + expect("("); + var ex = expression(); + expect(")"); + return ex; + }; + + function add_tokens(str, start, end) { + return new NodeWithToken(str, start, end); + }; + + var statement = embed_tokens ? function() { + var start = S.token; + var stmt = $statement(); + stmt[0] = add_tokens(stmt[0], start, prev()); + return stmt; + } : $statement; + + function $statement() { + if (is("operator", "/")) { + S.peeked = null; + S.token = S.input(true); // force regexp + } + switch (S.token.type) { + case "num": + case "string": + case "regexp": + case "operator": + case "atom": + return simple_statement(); + + case "name": + return is_token(peek(), "punc", ":") + ? labeled_statement(prog1(S.token.value, next, next)) + : simple_statement(); + + case "punc": + switch (S.token.value) { + case "{": + return as("block", block_()); + case "[": + case "(": + return simple_statement(); + case ";": + next(); + return as("block"); + default: + unexpected(); + } + + case "keyword": + switch (prog1(S.token.value, next)) { + case "break": + return break_cont("break"); + + case "continue": + return break_cont("continue"); + + case "debugger": + semicolon(); + return as("debugger"); + + case "do": + return (function(body){ + expect_token("keyword", "while"); + return as("do", prog1(parenthesised, semicolon), body); + })(in_loop(statement)); + + case "for": + return for_(); + + case "function": + return function_(true); + + case "if": + return if_(); + + case "return": + if (S.in_function == 0) + croak("'return' outside of function"); + return as("return", + is("punc", ";") + ? (next(), null) + : can_insert_semicolon() + ? null + : prog1(expression, semicolon)); + + case "switch": + return as("switch", parenthesised(), switch_block_()); + + case "throw": + return as("throw", prog1(expression, semicolon)); + + case "try": + return try_(); + + case "var": + return prog1(var_, semicolon); + + case "const": + return prog1(const_, semicolon); + + case "while": + return as("while", parenthesised(), in_loop(statement)); + + case "with": + return as("with", parenthesised(), statement()); + + default: + unexpected(); + } + } + }; + + function labeled_statement(label) { + S.labels.push(label); + var start = S.token, stat = statement(); + if (strict_mode && !HOP(STATEMENTS_WITH_LABELS, stat[0])) + unexpected(start); + S.labels.pop(); + return as("label", label, stat); + }; + + function simple_statement() { + return as("stat", prog1(expression, semicolon)); + }; + + function break_cont(type) { + var name = is("name") ? S.token.value : null; + if (name != null) { + next(); + if (!member(name, S.labels)) + croak("Label " + name + " without matching loop or statement"); + } + else if (S.in_loop == 0) + croak(type + " not inside a loop or switch"); + semicolon(); + return as(type, name); + }; + + function for_() { + expect("("); + var has_var = is("keyword", "var"); + if (has_var) + next(); + if (is("name") && is_token(peek(), "operator", "in")) { + // for (i in foo) + var name = S.token.value; + next(); next(); + var obj = expression(); + expect(")"); + return as("for-in", has_var, name, obj, in_loop(statement)); + } else { + // classic for + var init = is("punc", ";") ? null : has_var ? var_() : expression(); + expect(";"); + var test = is("punc", ";") ? null : expression(); + expect(";"); + var step = is("punc", ")") ? null : expression(); + expect(")"); + return as("for", init, test, step, in_loop(statement)); + } + }; + + function function_(in_statement) { + var name = is("name") ? prog1(S.token.value, next) : null; + if (in_statement && !name) + unexpected(); + expect("("); + return as(in_statement ? "defun" : "function", + name, + // arguments + (function(first, a){ + while (!is("punc", ")")) { + if (first) first = false; else expect(","); + if (!is("name")) unexpected(); + a.push(S.token.value); + next(); + } + next(); + return a; + })(true, []), + // body + (function(){ + ++S.in_function; + var loop = S.in_loop; + S.in_loop = 0; + var a = block_(); + --S.in_function; + S.in_loop = loop; + return a; + })()); + }; + + function if_() { + var cond = parenthesised(), body = statement(), belse; + if (is("keyword", "else")) { + next(); + belse = statement(); + } + return as("if", cond, body, belse); + }; + + function block_() { + expect("{"); + var a = []; + while (!is("punc", "}")) { + if (is("eof")) unexpected(); + a.push(statement()); + } + next(); + return a; + }; + + var switch_block_ = curry(in_loop, function(){ + expect("{"); + var a = [], cur = null; + while (!is("punc", "}")) { + if (is("eof")) unexpected(); + if (is("keyword", "case")) { + next(); + cur = []; + a.push([ expression(), cur ]); + expect(":"); + } + else if (is("keyword", "default")) { + next(); + expect(":"); + cur = []; + a.push([ null, cur ]); + } + else { + if (!cur) unexpected(); + cur.push(statement()); + } + } + next(); + return a; + }); + + function try_() { + var body = block_(), bcatch, bfinally; + if (is("keyword", "catch")) { + next(); + expect("("); + if (!is("name")) + croak("Name expected"); + var name = S.token.value; + next(); + expect(")"); + bcatch = [ name, block_() ]; + } + if (is("keyword", "finally")) { + next(); + bfinally = block_(); + } + if (!bcatch && !bfinally) + croak("Missing catch/finally blocks"); + return as("try", body, bcatch, bfinally); + }; + + function vardefs() { + var a = []; + for (;;) { + if (!is("name")) + unexpected(); + var name = S.token.value; + next(); + if (is("operator", "=")) { + next(); + a.push([ name, expression(false) ]); + } else { + a.push([ name ]); + } + if (!is("punc", ",")) + break; + next(); + } + return a; + }; + + function var_() { + return as("var", vardefs()); + }; + + function const_() { + return as("const", vardefs()); + }; + + function new_() { + var newexp = expr_atom(false), args; + if (is("punc", "(")) { + next(); + args = expr_list(")"); + } else { + args = []; + } + return subscripts(as("new", newexp, args), true); + }; + + function expr_atom(allow_calls) { + if (is("operator", "new")) { + next(); + return new_(); + } + if (is("operator") && HOP(UNARY_PREFIX, S.token.value)) { + return make_unary("unary-prefix", + prog1(S.token.value, next), + expr_atom(allow_calls)); + } + if (is("punc")) { + switch (S.token.value) { + case "(": + next(); + return subscripts(prog1(expression, curry(expect, ")")), allow_calls); + case "[": + next(); + return subscripts(array_(), allow_calls); + case "{": + next(); + return subscripts(object_(), allow_calls); + } + unexpected(); + } + if (is("keyword", "function")) { + next(); + return subscripts(function_(false), allow_calls); + } + if (HOP(ATOMIC_START_TOKEN, S.token.type)) { + var atom = S.token.type == "regexp" + ? as("regexp", S.token.value[0], S.token.value[1]) + : as(S.token.type, S.token.value); + return subscripts(prog1(atom, next), allow_calls); + } + unexpected(); + }; + + function expr_list(closing, allow_trailing_comma) { + var first = true, a = []; + while (!is("punc", closing)) { + if (first) first = false; else expect(","); + if (allow_trailing_comma && is("punc", closing)) + break; + a.push(expression(false)); + } + next(); + return a; + }; + + function array_() { + return as("array", expr_list("]", !strict_mode)); + }; + + function object_() { + var first = true, a = []; + while (!is("punc", "}")) { + if (first) first = false; else expect(","); + if (!strict_mode && is("punc", "}")) + // allow trailing comma + break; + var type = S.token.type; + var name = as_property_name(); + if (type == "name" && (name == "get" || name == "set") && !is("punc", ":")) { + a.push([ as_name(), function_(false), name ]); + } else { + expect(":"); + a.push([ name, expression(false) ]); + } + } + next(); + return as("object", a); + }; + + function as_property_name() { + switch (S.token.type) { + case "num": + case "string": + return prog1(S.token.value, next); + } + return as_name(); + }; + + function as_name() { + switch (S.token.type) { + case "name": + case "operator": + case "keyword": + case "atom": + return prog1(S.token.value, next); + default: + unexpected(); + } + }; + + function subscripts(expr, allow_calls) { + if (is("punc", ".")) { + next(); + return subscripts(as("dot", expr, as_name()), allow_calls); + } + if (is("punc", "[")) { + next(); + return subscripts(as("sub", expr, prog1(expression, curry(expect, "]"))), allow_calls); + } + if (allow_calls && is("punc", "(")) { + next(); + return subscripts(as("call", expr, expr_list(")")), true); + } + if (allow_calls && is("operator") && HOP(UNARY_POSTFIX, S.token.value)) { + return prog1(curry(make_unary, "unary-postfix", S.token.value, expr), + next); + } + return expr; + }; + + function make_unary(tag, op, expr) { + if ((op == "++" || op == "--") && !is_assignable(expr)) + croak("Invalid use of " + op + " operator"); + return as(tag, op, expr); + }; + + function expr_op(left, min_prec) { + var op = is("operator") ? S.token.value : null; + var prec = op != null ? PRECEDENCE[op] : null; + if (prec != null && prec > min_prec) { + next(); + var right = expr_op(expr_atom(true), prec); + return expr_op(as("binary", op, left, right), min_prec); + } + return left; + }; + + function expr_ops() { + return expr_op(expr_atom(true), 0); + }; + + function maybe_conditional() { + var expr = expr_ops(); + if (is("operator", "?")) { + next(); + var yes = expression(false); + expect(":"); + return as("conditional", expr, yes, expression(false)); + } + return expr; + }; + + function is_assignable(expr) { + switch (expr[0]) { + case "dot": + case "sub": + return true; + case "name": + return expr[1] != "this"; + } + }; + + function maybe_assign() { + var left = maybe_conditional(), val = S.token.value; + if (is("operator") && HOP(ASSIGNMENT, val)) { + if (is_assignable(left)) { + next(); + return as("assign", ASSIGNMENT[val], left, maybe_assign()); + } + croak("Invalid assignment"); + } + return left; + }; + + function expression(commas) { + if (arguments.length == 0) + commas = true; + var expr = maybe_assign(); + if (commas && is("punc", ",")) { + next(); + return as("seq", expr, expression()); + } + return expr; + }; + + function in_loop(cont) { + try { + ++S.in_loop; + return cont(); + } finally { + --S.in_loop; + } + }; + + return as("toplevel", (function(a){ + while (!is("eof")) + a.push(statement()); + return a; + })([])); + +}; + +/* -----[ Utilities ]----- */ + +function curry(f) { + var args = slice(arguments, 1); + return function() { return f.apply(this, args.concat(slice(arguments))); }; +}; + +function prog1(ret) { + if (ret instanceof Function) + ret = ret(); + for (var i = 1, n = arguments.length; --n > 0; ++i) + arguments[i](); + return ret; +}; + +function array_to_hash(a) { + var ret = {}; + for (var i = 0; i < a.length; ++i) + ret[a[i]] = true; + return ret; +}; + +function slice(a, start) { + return Array.prototype.slice.call(a, start == null ? 0 : start); +}; + +function characters(str) { + return str.split(""); +}; + +function member(name, array) { + for (var i = array.length; --i >= 0;) + if (array[i] === name) + return true; + return false; +}; + +function HOP(obj, prop) { + return Object.prototype.hasOwnProperty.call(obj, prop); +}; + +/* -----[ Exports ]----- */ + +exports.tokenizer = tokenizer; +exports.parse = parse; +exports.slice = slice; +exports.curry = curry; +exports.member = member; +exports.array_to_hash = array_to_hash; +exports.PRECEDENCE = PRECEDENCE; +exports.KEYWORDS_ATOM = KEYWORDS_ATOM; +exports.RESERVED_WORDS = RESERVED_WORDS; +exports.KEYWORDS = KEYWORDS; +exports.ATOMIC_START_TOKEN = ATOMIC_START_TOKEN; +exports.OPERATORS = OPERATORS; +exports.is_alphanumeric_char = is_alphanumeric_char;