(function(){ var ACCESSORS, ASSIGNMENT, BEFORE_WHEN, CALLABLE, CODE, COFFEE_KEYWORDS, COMMENT, COMMENT_CLEANER, HEREDOC, HEREDOC_INDENT, IDENTIFIER, JS, JS_CLEANER, JS_FORBIDDEN, JS_KEYWORDS, KEYWORDS, LAST_DENT, LAST_DENTS, Lexer, MULTILINER, MULTI_DENT, NOT_REGEX, NO_NEWLINE, NUMBER, OPERATOR, REGEX, RESERVED, Rewriter, STRING, STRING_NEWLINES, WHITESPACE, compact, count, include; // The CoffeeScript Lexer. Uses a series of token-matching regexes to attempt // matches against the beginning of the source code. When a match is found, // a token is produced, we consume the match, and start again. Tokens are in the // form: // [tag, value, line_number] // Which is a format that can be fed directly into [Jison](http://github.com/zaach/jison). // Set up the Lexer for both Node.js and the browser, depending on where we are. if ((typeof process !== "undefined" && process !== null)) { Rewriter = require('./rewriter').Rewriter; } else { this.exports = this; Rewriter = this.Rewriter; } // Constants // --------- // Keywords that CoffeeScript shares in common with JavaScript. JS_KEYWORDS = ["if", "else", "true", "false", "new", "return", "try", "catch", "finally", "throw", "break", "continue", "for", "in", "while", "delete", "instanceof", "typeof", "switch", "super", "extends", "class"]; // CoffeeScript-only keywords, which we're more relaxed about allowing. They can't // be used standalone, but you can reference them as an attached property. COFFEE_KEYWORDS = ["then", "unless", "yes", "no", "on", "off", "and", "or", "is", "isnt", "not", "of", "by", "where", "when"]; // The combined list of keywords is the superset that gets passed verbatim to // the parser. KEYWORDS = JS_KEYWORDS.concat(COFFEE_KEYWORDS); // The list of keywords that are reserved by JavaScript, but not used, or are // used by CoffeeScript internally. We throw an error when these are encountered, // to avoid having a JavaScript error at runtime. RESERVED = ["case", "default", "do", "function", "var", "void", "with", "const", "let", "debugger", "enum", "export", "import", "native", "__extends", "__hasProp"]; // The superset of both JavaScript keywords and reserved words, none of which may // be used as identifiers or properties. JS_FORBIDDEN = JS_KEYWORDS.concat(RESERVED); // Token matching regexes. IDENTIFIER = /^([a-zA-Z$_](\w|\$)*)/; NUMBER = /^(\b((0(x|X)[0-9a-fA-F]+)|([0-9]+(\.[0-9]+)?(e[+\-]?[0-9]+)?)))\b/i; STRING = /^(""|''|"([\s\S]*?)([^\\]|\\\\)"|'([\s\S]*?)([^\\]|\\\\)')/; HEREDOC = /^("{6}|'{6}|"{3}\n?([\s\S]*?)\n?([ \t]*)"{3}|'{3}\n?([\s\S]*?)\n?([ \t]*)'{3})/; JS = /^(``|`([\s\S]*?)([^\\]|\\\\)`)/; OPERATOR = /^([+\*&|\/\-%=<>:!?]+)/; WHITESPACE = /^([ \t]+)/; COMMENT = /^(((\n?[ \t]*)?#[^\n]*)+)/; CODE = /^((-|=)>)/; REGEX = /^(\/(\S.*?)?([^\\]|\\\\)\/[imgy]{0,4})/; MULTI_DENT = /^((\n([ \t]*))+)(\.)?/; LAST_DENTS = /\n([ \t]*)/g; LAST_DENT = /\n([ \t]*)/; ASSIGNMENT = /^(:|=)$/; // Token cleaning regexes. JS_CLEANER = /(^`|`$)/g; MULTILINER = /\n/g; STRING_NEWLINES = /\n[ \t]*/g; COMMENT_CLEANER = /(^[ \t]*#|\n[ \t]*$)/mg; NO_NEWLINE = /^([+\*&|\/\-%=<>:!.\\][<>=&|]*|and|or|is|isnt|not|delete|typeof|instanceof)$/; HEREDOC_INDENT = /^[ \t]+/mg; // Tokens which a regular expression will never immediately follow, but which // a division operator might. // See: http://www.mozilla.org/js/language/js20-2002-04/rationale/syntax.html#regular-expressions // Our list is shorter, due to sans-parentheses method calls. NOT_REGEX = ['NUMBER', 'REGEX', '++', '--', 'FALSE', 'NULL', 'TRUE']; // Tokens which could legitimately be invoked or indexed. A opening // parentheses or bracket following these tokens will be recorded as the start // of a function invocation or indexing operation. CALLABLE = ['IDENTIFIER', 'SUPER', ')', ']', '}', 'STRING', '@']; // Tokens that indicate an access -- keywords immediately following will be // treated as identifiers. ACCESSORS = ['PROPERTY_ACCESS', 'PROTOTYPE_ACCESS', 'SOAK_ACCESS', '@']; // Tokens that, when immediately preceding a `WHEN`, indicate that the `WHEN` // occurs at the start of a line. We disambiguate these from trailing whens to // avoid an ambiguity in the grammar. BEFORE_WHEN = ['INDENT', 'OUTDENT', 'TERMINATOR']; // The Lexer Class // --------------- // The Lexer class reads a stream of CoffeeScript and divvys it up into tagged // tokens. A minor bit of the ambiguity in the grammar has been avoided by // pushing some extra smarts into the Lexer. exports.Lexer = (function() { Lexer = function Lexer() { }; // Scan by attempting to match tokens one at a time. Slow and steady. Lexer.prototype.tokenize = function tokenize(code) { this.code = code; // The remainder of the source code. this.i = 0; // Current character position we're parsing. this.line = 0; // The current line. this.indent = 0; // The current indent level. this.indents = []; // The stack of all indent levels we are currently within. this.tokens = []; // Collection of all parsed tokens in the form ['TOKEN_TYPE', value, line] while (this.i < this.code.length) { this.chunk = this.code.slice(this.i); this.extract_next_token(); } this.close_indentation(); return (new Rewriter()).rewrite(this.tokens); }; // At every position, run through this list of attempted matches, // short-circuiting if any of them succeed. Lexer.prototype.extract_next_token = function extract_next_token() { if (this.identifier_token()) { return null; } if (this.number_token()) { return null; } if (this.heredoc_token()) { return null; } if (this.string_token()) { return null; } if (this.js_token()) { return null; } if (this.regex_token()) { return null; } if (this.comment_token()) { return null; } if (this.line_token()) { return null; } if (this.whitespace_token()) { return null; } return this.literal_token(); }; // Tokenizers // ---------- // Matches identifying literals: variables, keywords, method names, etc. Lexer.prototype.identifier_token = function identifier_token() { var id, tag; if (!((id = this.match(IDENTIFIER, 1)))) { return false; } this.name_access_type(); tag = 'IDENTIFIER'; if (include(KEYWORDS, id) && !(include(ACCESSORS, this.tag(0)) && !this.prev().spaced)) { tag = id.toUpperCase(); } if (include(RESERVED, id)) { this.identifier_error(id); } if (tag === 'WHEN' && include(BEFORE_WHEN, this.tag())) { tag = 'LEADING_WHEN'; } this.token(tag, id); this.i += id.length; return true; }; // Matches numbers, including decimals, hex, and exponential notation. Lexer.prototype.number_token = function number_token() { var number; if (!((number = this.match(NUMBER, 1)))) { return false; } this.token('NUMBER', number); this.i += number.length; return true; }; // Matches strings, including multi-line strings. Lexer.prototype.string_token = function string_token() { var escaped, string; if (!((string = this.match(STRING, 1)))) { return false; } escaped = string.replace(STRING_NEWLINES, " \\\n"); this.token('STRING', escaped); this.line += count(string, "\n"); this.i += string.length; return true; }; // Matches heredocs, adjusting indentation to the correct level. Lexer.prototype.heredoc_token = function heredoc_token() { var doc, match; if (!((match = this.chunk.match(HEREDOC)))) { return false; } doc = this.sanitize_heredoc(match[2] || match[4]); this.token('STRING', '"' + doc + '"'); this.line += count(match[1], "\n"); this.i += match[1].length; return true; }; // Matches interpolated JavaScript. Lexer.prototype.js_token = function js_token() { var script; if (!((script = this.match(JS, 1)))) { return false; } this.token('JS', script.replace(JS_CLEANER, '')); this.i += script.length; return true; }; // Matches regular expression literals. Lexer.prototype.regex_token = function regex_token() { var regex; if (!((regex = this.match(REGEX, 1)))) { return false; } if (include(NOT_REGEX, this.tag())) { return false; } this.token('REGEX', regex); this.i += regex.length; return true; }; // Matches and conumes comments. Lexer.prototype.comment_token = function comment_token() { var comment, lines; if (!((comment = this.match(COMMENT, 1)))) { return false; } this.line += (comment.match(MULTILINER) || []).length; lines = comment.replace(COMMENT_CLEANER, '').split(MULTILINER); this.token('COMMENT', compact(lines)); this.token('TERMINATOR', "\n"); this.i += comment.length; return true; }; // Matches newlines, indents, and outdents, and determines which is which. Lexer.prototype.line_token = function line_token() { var diff, indent, next_character, no_newlines, prev, size; if (!((indent = this.match(MULTI_DENT, 1)))) { return false; } this.line += indent.match(MULTILINER).length; this.i += indent.length; prev = this.prev(2); size = indent.match(LAST_DENTS).reverse()[0].match(LAST_DENT)[1].length; next_character = this.chunk.match(MULTI_DENT)[4]; no_newlines = next_character === '.' || (this.value() && this.value().match(NO_NEWLINE) && prev && (prev[0] !== '.') && !this.value().match(CODE)); if (size === this.indent) { if (no_newlines) { return this.suppress_newlines(indent); } return this.newline_token(indent); } else if (size > this.indent) { if (no_newlines) { return this.suppress_newlines(indent); } diff = size - this.indent; this.token('INDENT', diff); this.indents.push(diff); } else { this.outdent_token(this.indent - size, no_newlines); } this.indent = size; return true; }; // Record an outdent token or tokens, if we happen to be moving back inwards // past multiple recorded indents. Lexer.prototype.outdent_token = function outdent_token(move_out, no_newlines) { var last_indent; while (move_out > 0 && this.indents.length) { last_indent = this.indents.pop(); this.token('OUTDENT', last_indent); move_out -= last_indent; } if (!(this.tag() === 'TERMINATOR' || no_newlines)) { this.token('TERMINATOR', "\n"); } return true; }; // Matches and consumes non-meaningful whitespace. Tag the previous token // as being "spaced", because there are some cases where it makes a difference. Lexer.prototype.whitespace_token = function whitespace_token() { var prev, space; if (!((space = this.match(WHITESPACE, 1)))) { return false; } prev = this.prev(); if (prev) { prev.spaced = true; } this.i += space.length; return true; }; // Generate a newline token. Multiple newlines get merged together. Lexer.prototype.newline_token = function newline_token(newlines) { if (!(this.tag() === 'TERMINATOR')) { this.token('TERMINATOR', "\n"); } return true; }; // Use a `\` at a line-ending to suppress the newline. // The slash is removed here once its job is done. Lexer.prototype.suppress_newlines = function suppress_newlines(newlines) { if (this.value() === "\\") { this.tokens.pop(); } return true; }; // We treat all other single characters as a token. Eg.: `( ) , . !` // Multi-character operators are also literal tokens, so that Jison can assign // the proper order of operations. Lexer.prototype.literal_token = function literal_token() { var match, not_spaced, tag, value; match = this.chunk.match(OPERATOR); value = match && match[1]; if (value && value.match(CODE)) { this.tag_parameters(); } value = value || this.chunk.substr(0, 1); not_spaced = !this.prev() || !this.prev().spaced; tag = value; if (value.match(ASSIGNMENT)) { tag = 'ASSIGN'; if (include(JS_FORBIDDEN, this.value)) { this.assignment_error(); } } else if (value === ';') { tag = 'TERMINATOR'; } else if (value === '[' && this.tag() === '?' && not_spaced) { tag = 'SOAKED_INDEX_START'; this.soaked_index = true; this.tokens.pop(); } else if (value === ']' && this.soaked_index) { tag = 'SOAKED_INDEX_END'; this.soaked_index = false; } else if (include(CALLABLE, this.tag()) && not_spaced) { if (value === '(') { tag = 'CALL_START'; } if (value === '[') { tag = 'INDEX_START'; } } this.token(tag, value); this.i += value.length; return true; }; // Token Manipulators // ------------------ // As we consume a new `IDENTIFIER`, look at the previous token to determine // if it's a special kind of accessor. Lexer.prototype.name_access_type = function name_access_type() { if (this.value() === '::') { this.tag(1, 'PROTOTYPE_ACCESS'); } if (this.value() === '.' && !(this.value(2) === '.')) { if (this.tag(2) === '?') { this.tag(1, 'SOAK_ACCESS'); return this.tokens.splice(-2, 1); } else { return this.tag(1, 'PROPERTY_ACCESS'); } } }; // Sanitize a heredoc by escaping double quotes and erasing all external // indentation on the left-hand side. Lexer.prototype.sanitize_heredoc = function sanitize_heredoc(doc) { var indent; indent = (doc.match(HEREDOC_INDENT) || ['']).sort()[0]; return doc.replace(new RegExp("^" + indent, 'gm'), '').replace(MULTILINER, "\\n").replace(/"/g, '\\"'); }; // A source of ambiguity in our grammar was parameter lists in function // definitions (as opposed to argument lists in function calls). Tag // parameter identifiers in order to avoid this. Also, parameter lists can // make use of splats. Lexer.prototype.tag_parameters = function tag_parameters() { var _a, i, tok; if (this.tag() !== ')') { return null; } i = 0; while (true) { i += 1; tok = this.prev(i); if (!tok) { return null; } if ((_a = tok[0]) === 'IDENTIFIER') { tok[0] = 'PARAM'; } else if (_a === ')') { tok[0] = 'PARAM_END'; } else if (_a === '(') { return (tok[0] = 'PARAM_START'); } } return true; }; // Close up all remaining open blocks at the end of the file. Lexer.prototype.close_indentation = function close_indentation() { return this.outdent_token(this.indent); }; // Error for when you try to use a forbidden word in JavaScript as // an identifier. Lexer.prototype.identifier_error = function identifier_error(word) { throw new Error('SyntaxError: Reserved word "' + word + '" on line ' + this.line); }; // Error for when you try to assign to a reserved word in JavaScript, // like "function" or "default". Lexer.prototype.assignment_error = function assignment_error() { throw new Error('SyntaxError: Reserved word "' + this.value() + '" on line ' + this.line + ' can\'t be assigned'); }; // Helpers // ------- // Add a token to the results, taking note of the line number. Lexer.prototype.token = function token(tag, value) { return this.tokens.push([tag, value, this.line]); }; // Peek at a tag in the current token stream. Lexer.prototype.tag = function tag(index, tag) { var tok; if (!((tok = this.prev(index)))) { return null; } if ((typeof tag !== "undefined" && tag !== null)) { return (tok[0] = tag); } return tok[0]; }; // Peek at a value in the current token stream. Lexer.prototype.value = function value(index, val) { var tok; if (!((tok = this.prev(index)))) { return null; } if ((typeof val !== "undefined" && val !== null)) { return (tok[1] = val); } return tok[1]; }; // Peek at a previous token, entire. Lexer.prototype.prev = function prev(index) { return this.tokens[this.tokens.length - (index || 1)]; }; // Attempt to match a string against the current chunk, returning the indexed // match if successful, and `false` otherwise. Lexer.prototype.match = function match(regex, index) { var m; if (!((m = this.chunk.match(regex)))) { return false; } return m ? m[index] : false; }; return Lexer; }).call(this); // Utility Functions // ----------------- // Does a list include a value? include = function include(list, value) { return list.indexOf(value) >= 0; }; // Trim out all falsy values from an array. compact = function compact(array) { var _a, _b, _c, _d, item; _a = []; _b = array; for (_c = 0, _d = _b.length; _c < _d; _c++) { item = _b[_c]; if (item) { _a.push(item); } } return _a; }; // Count the number of occurences of a character in a string. count = function count(string, letter) { var num, pos; num = 0; pos = string.indexOf(letter); while (pos !== -1) { num += 1; pos = string.indexOf(letter, pos + 1); } return num; }; })();