(function(){ var BALANCED_PAIRS, EXPRESSION_CLOSE, EXPRESSION_END, EXPRESSION_START, IMPLICIT_BLOCK, IMPLICIT_CALL, IMPLICIT_END, IMPLICIT_FUNC, INVERSES, Rewriter, SINGLE_CLOSERS, SINGLE_LINERS, _a, _b, _c, _d, _e, _f, _g, _h, _i, _j, _k, helpers, include, pair; var __slice = Array.prototype.slice, __bind = function(func, obj, args) { return function() { return func.apply(obj || {}, args ? args.concat(__slice.call(arguments, 0)) : arguments); }; }, __hasProp = Object.prototype.hasOwnProperty; // The CoffeeScript language has a good deal of optional syntax, implicit syntax, // and shorthand syntax. This can greatly complicate a grammar and bloat // the resulting parse table. Instead of making the parser handle it all, we take // a series of passes over the token stream, using this **Rewriter** to convert // shorthand into the unambiguous long form, add implicit indentation and // parentheses, balance incorrect nestings, and generally clean things up. // Set up exported variables for both Node.js and the browser. if ((typeof process !== "undefined" && process !== null)) { helpers = require('./helpers').helpers; } else { this.exports = this; helpers = this.helpers; } // Import the helpers we need. include = helpers.include; // The **Rewriter** class is used by the [Lexer](lexer.html), directly against // its internal array of tokens. exports.Rewriter = (function() { Rewriter = function Rewriter() { }; // Rewrite the token stream in multiple passes, one logical filter at // a time. This could certainly be changed into a single pass through the // stream, with a big ol' efficient switch, but it's much nicer to work with // like this. The order of these passes matters -- indentation must be // corrected before implicit parentheses can be wrapped around blocks of code. Rewriter.prototype.rewrite = function rewrite(tokens) { this.tokens = tokens; this.adjust_comments(); this.remove_leading_newlines(); this.remove_mid_expression_newlines(); this.close_open_calls_and_indexes(); this.add_implicit_indentation(); this.add_implicit_parentheses(); this.ensure_balance(BALANCED_PAIRS); this.rewrite_closing_parens(); return this.tokens; }; // Rewrite the token stream, looking one token ahead and behind. // Allow the return value of the block to tell us how many tokens to move // forwards (or backwards) in the stream, to make sure we don't miss anything // as tokens are inserted and removed, and the stream changes length under // our feet. Rewriter.prototype.scan_tokens = function scan_tokens(block) { var i, move; i = 0; while (true) { if (!(this.tokens[i])) { break; } move = block(this.tokens[i - 1], this.tokens[i], this.tokens[i + 1], i); i += move; } return true; }; // Massage newlines and indentations so that comments don't have to be // correctly indented, or appear on a line of their own. Rewriter.prototype.adjust_comments = function adjust_comments() { return this.scan_tokens(__bind(function(prev, token, post, i) { var after; if (!(token[0] === 'COMMENT')) { return 1; } after = this.tokens[i + 2]; if (after && after[0] === 'INDENT') { this.tokens.splice(i + 2, 1); this.tokens.splice(i, 0, after); return 1; } else if (prev && prev[0] !== 'TERMINATOR' && prev[0] !== 'INDENT' && prev[0] !== 'OUTDENT') { this.tokens.splice(i, 0, ['TERMINATOR', "\n", prev[2]]); return 2; } else { return 1; } }, this)); }; // Leading newlines would introduce an ambiguity in the grammar, so we // dispatch them here. Rewriter.prototype.remove_leading_newlines = function remove_leading_newlines() { var _a; _a = []; while (this.tokens[0] && this.tokens[0][0] === 'TERMINATOR') { _a.push(this.tokens.shift()); } return _a; }; // Some blocks occur in the middle of expressions -- when we're expecting // this, remove their trailing newlines. Rewriter.prototype.remove_mid_expression_newlines = function remove_mid_expression_newlines() { return this.scan_tokens(__bind(function(prev, token, post, i) { if (!(post && include(EXPRESSION_CLOSE, post[0]) && token[0] === 'TERMINATOR')) { return 1; } this.tokens.splice(i, 1); return 0; }, this)); }; // The lexer has tagged the opening parenthesis of a method call, and the // opening bracket of an indexing operation. Match them with their paired // close. Rewriter.prototype.close_open_calls_and_indexes = function close_open_calls_and_indexes() { var brackets, parens; parens = [0]; brackets = [0]; return this.scan_tokens(__bind(function(prev, token, post, i) { var _a; if ((_a = token[0]) === 'CALL_START') { parens.push(0); } else if (_a === 'INDEX_START') { brackets.push(0); } else if (_a === '(') { parens[parens.length - 1] += 1; } else if (_a === '[') { brackets[brackets.length - 1] += 1; } else if (_a === ')') { if (parens[parens.length - 1] === 0) { parens.pop(); token[0] = 'CALL_END'; } else { parens[parens.length - 1] -= 1; } } else if (_a === ']') { if (brackets[brackets.length - 1] === 0) { brackets.pop(); token[0] = 'INDEX_END'; } else { brackets[brackets.length - 1] -= 1; } } return 1; }, this)); }; // Methods may be optionally called without parentheses, for simple cases. // Insert the implicit parentheses here, so that the parser doesn't have to // deal with them. Rewriter.prototype.add_implicit_parentheses = function add_implicit_parentheses() { var calls, parens, stack, start_parens; stack = [0]; calls = 0; parens = 0; start_parens = 0; return this.scan_tokens(__bind(function(prev, token, post, i) { var _a, _b, _c, idx, last, open, size, stack_pointer, tag, tmp; tag = token[0]; if (tag === 'CALL_START') { calls += 1; } else if (tag === 'CALL_END') { calls -= 1; } else if (tag === '(') { parens += 1; } else if (tag === ')') { parens -= 1; } else if (tag === 'INDENT') { stack.push(0); } else if (tag === 'OUTDENT') { last = stack.pop(); stack[stack.length - 1] += last; } open = stack[stack.length - 1] > 0; if (!(typeof post !== "undefined" && post !== null) || (start_parens > parens) || (parens === 0 && include(IMPLICIT_END, tag))) { if (tag === 'INDENT' && prev && include(IMPLICIT_BLOCK, prev[0])) { return 1; } if (tag === 'OUTDENT' && token.generated) { return 1; } if (open || tag === 'INDENT') { idx = tag === 'OUTDENT' ? i + 1 : i; stack_pointer = tag === 'INDENT' ? 2 : 1; _b = 0; _c = stack[stack.length - stack_pointer]; for (_a = 0, tmp = _b; (_b <= _c ? tmp < _c : tmp > _c); (_b <= _c ? tmp += 1 : tmp -= 1), _a++) { this.tokens.splice(idx, 0, ['CALL_END', ')', token[2]]); } size = stack[stack.length - stack_pointer] + 1; stack[stack.length - stack_pointer] = 0; return size; } } if (!(prev && include(IMPLICIT_FUNC, prev[0]) && include(IMPLICIT_CALL, tag))) { return 1; } calls = 0; start_parens = tag === '(' ? parens - 1 : parens; this.tokens.splice(i, 0, ['CALL_START', '(', token[2]]); stack[stack.length - 1] += 1; return 2; }, this)); }; // Because our grammar is LALR(1), it can't handle some single-line // expressions that lack ending delimiters. The **Rewriter** adds the implicit // blocks, so it doesn't need to. ')' can close a single-line block, // but we need to make sure it's balanced. Rewriter.prototype.add_implicit_indentation = function add_implicit_indentation() { return this.scan_tokens(__bind(function(prev, token, post, i) { var idx, insertion, outdent, parens, pre, starter, tok; if (!(include(SINGLE_LINERS, token[0]) && post[0] !== 'INDENT' && !(token[0] === 'ELSE' && post[0] === 'IF'))) { return 1; } starter = token[0]; this.tokens.splice(i + 1, 0, ['INDENT', 2, token[2]]); idx = i + 1; parens = 0; while (true) { idx += 1; tok = this.tokens[idx]; pre = this.tokens[idx - 1]; if ((!tok || (include(SINGLE_CLOSERS, tok[0]) && tok[1] !== ';') || (tok[0] === ')' && parens === 0)) && !(starter === 'ELSE' && tok[0] === 'ELSE')) { insertion = pre[0] === "," ? idx - 1 : idx; outdent = ['OUTDENT', 2, token[2]]; outdent.generated = true; this.tokens.splice(insertion, 0, outdent); break; } if (tok[0] === '(') { parens += 1; } if (tok[0] === ')') { parens -= 1; } } if (!(token[0] === 'THEN')) { return 1; } this.tokens.splice(i, 1); return 0; }, this)); }; // Ensure that all listed pairs of tokens are correctly balanced throughout // the course of the token stream. Rewriter.prototype.ensure_balance = function ensure_balance(pairs) { var _a, _b, key, levels, line, open, open_line, unclosed, value; levels = {}; open_line = {}; this.scan_tokens(__bind(function(prev, token, post, i) { var _a, _b, _c, _d, close, open, pair; _b = pairs; for (_a = 0, _c = _b.length; _a < _c; _a++) { pair = _b[_a]; _d = pair; open = _d[0]; close = _d[1]; levels[open] = levels[open] || 0; if (token[0] === open) { if (levels[open] === 0) { open_line[open] = token[2]; } levels[open] += 1; } if (token[0] === close) { levels[open] -= 1; } if (levels[open] < 0) { throw new Error(("too many " + (token[1]) + " on line " + (token[2] + 1))); } } return 1; }, this)); unclosed = (function() { _a = []; _b = levels; for (key in _b) { if (__hasProp.call(_b, key)) { value = _b[key]; value > 0 ? _a.push(key) : null; }} return _a; }).call(this); if (unclosed.length) { open = unclosed[0]; line = open_line[open] + 1; throw new Error(("unclosed " + open + " on line " + line)); } }; // We'd like to support syntax like this: // el.click((event) -> // el.hide()) // In order to accomplish this, move outdents that follow closing parens // inwards, safely. The steps to accomplish this are: // 1. Check that all paired tokens are balanced and in order. // 2. Rewrite the stream with a stack: if you see an `EXPRESSION_START`, add it // to the stack. If you see an `EXPRESSION_END`, pop the stack and replace // it with the inverse of what we've just popped. // 3. Keep track of "debt" for tokens that we manufacture, to make sure we end // up balanced in the end. Rewriter.prototype.rewrite_closing_parens = function rewrite_closing_parens() { var _a, debt, key, stack, val; stack = []; debt = {}; _a = INVERSES; for (key in _a) { if (__hasProp.call(_a, key)) { val = _a[key]; (debt[key] = 0); }} return this.scan_tokens(__bind(function(prev, token, post, i) { var inv, match, mtag, tag; tag = token[0]; inv = INVERSES[token[0]]; if (include(EXPRESSION_START, tag)) { stack.push(token); return 1; } else if (include(EXPRESSION_END, tag)) { if (debt[inv] > 0) { debt[inv] -= 1; this.tokens.splice(i, 1); return 0; } else { match = stack.pop(); mtag = match[0]; if (tag === INVERSES[mtag]) { return 1; } debt[mtag] += 1; val = mtag === 'INDENT' ? match[1] : INVERSES[mtag]; this.tokens.splice(i, 0, [INVERSES[mtag], val]); return 1; } } else { return 1; } }, this)); }; return Rewriter; }).call(this); // Constants // --------- // List of the token pairs that must be balanced. BALANCED_PAIRS = [['(', ')'], ['[', ']'], ['{', '}'], ['INDENT', 'OUTDENT'], ['PARAM_START', 'PARAM_END'], ['CALL_START', 'CALL_END'], ['INDEX_START', 'INDEX_END'], ['SOAKED_INDEX_START', 'SOAKED_INDEX_END']]; // The inverse mappings of `BALANCED_PAIRS` we're trying to fix up, so we can // look things up from either end. INVERSES = {}; _b = BALANCED_PAIRS; for (_a = 0, _c = _b.length; _a < _c; _a++) { pair = _b[_a]; INVERSES[pair[0]] = pair[1]; INVERSES[pair[1]] = pair[0]; } // The tokens that signal the start of a balanced pair. EXPRESSION_START = (function() { _d = []; _f = BALANCED_PAIRS; for (_e = 0, _g = _f.length; _e < _g; _e++) { pair = _f[_e]; _d.push(pair[0]); } return _d; }).call(this); // The tokens that signal the end of a balanced pair. EXPRESSION_END = (function() { _h = []; _j = BALANCED_PAIRS; for (_i = 0, _k = _j.length; _i < _k; _i++) { pair = _j[_i]; _h.push(pair[1]); } return _h; }).call(this); // Tokens that indicate the close of a clause of an expression. EXPRESSION_CLOSE = ['CATCH', 'WHEN', 'ELSE', 'FINALLY'].concat(EXPRESSION_END); // Tokens that, if followed by an `IMPLICIT_CALL`, indicate a function invocation. IMPLICIT_FUNC = ['IDENTIFIER', 'SUPER', ')', 'CALL_END', ']', 'INDEX_END', '<-']; // If preceded by an `IMPLICIT_FUNC`, indicates a function invocation. IMPLICIT_CALL = ['IDENTIFIER', 'NUMBER', 'STRING', 'JS', 'REGEX', 'NEW', 'PARAM_START', 'TRY', 'DELETE', 'TYPEOF', 'SWITCH', 'EXTENSION', 'TRUE', 'FALSE', 'YES', 'NO', 'ON', 'OFF', '!', '!!', 'NOT', 'THIS', 'NULL', '@', '->', '=>', '[', '(', '{']; // Tokens indicating that the implicit call must enclose a block of expressions. IMPLICIT_BLOCK = ['->', '=>', '{', '[', ',']; // Tokens that always mark the end of an implicit call for single-liners. IMPLICIT_END = ['IF', 'UNLESS', 'FOR', 'WHILE', 'TERMINATOR', 'INDENT', 'OUTDENT']; // Single-line flavors of block expressions that have unclosed endings. // The grammar can't disambiguate them, so we insert the implicit indentation. SINGLE_LINERS = ['ELSE', "->", "=>", 'TRY', 'FINALLY', 'THEN']; SINGLE_CLOSERS = ['TERMINATOR', 'CATCH', 'FINALLY', 'ELSE', 'OUTDENT', 'LEADING_WHEN']; })();