(function(){ var BALANCED_PAIRS, EXPRESSION_CLOSE, EXPRESSION_START, EXPRESSION_TAIL, IMPLICIT_CALL, IMPLICIT_END, IMPLICIT_FUNC, INVERSES, SINGLE_CLOSERS, SINGLE_LINERS, __a, __b, __c, __d, __e, __f, __g, __h, pair, re; var __hasProp = Object.prototype.hasOwnProperty; // In order to keep the grammar simple, the stream of tokens that the Lexer // emits is rewritten by the Rewriter, smoothing out ambiguities, mis-nested // indentation, and single-line flavors of expressions. exports.Rewriter = (re = function re() { }); // Tokens that must be balanced. BALANCED_PAIRS = [['(', ')'], ['[', ']'], ['{', '}'], ['INDENT', 'OUTDENT'], ['PARAM_START', 'PARAM_END'], ['CALL_START', 'CALL_END'], ['INDEX_START', 'INDEX_END']]; // Tokens that signal the start of a balanced pair. EXPRESSION_START = (function() { __a = []; __b = BALANCED_PAIRS; for (__c = 0; __c < __b.length; __c++) { pair = __b[__c]; __a.push(pair[0]); } return __a; }).call(this); // Tokens that signal the end of a balanced pair. EXPRESSION_TAIL = (function() { __d = []; __e = BALANCED_PAIRS; for (__f = 0; __f < __e.length; __f++) { pair = __e[__f]; __d.push(pair[1]); } return __d; }).call(this); // Tokens that indicate the close of a clause of an expression. EXPRESSION_CLOSE = ['CATCH', 'WHEN', 'ELSE', 'FINALLY'].concat(EXPRESSION_TAIL); // Tokens pairs that, in immediate succession, indicate an implicit call. IMPLICIT_FUNC = ['IDENTIFIER', 'SUPER', ')', 'CALL_END', ']', 'INDEX_END']; IMPLICIT_END = ['IF', 'UNLESS', 'FOR', 'WHILE', 'TERMINATOR', 'OUTDENT']; IMPLICIT_CALL = ['IDENTIFIER', 'NUMBER', 'STRING', 'JS', 'REGEX', 'NEW', 'PARAM_START', 'TRY', 'DELETE', 'TYPEOF', 'SWITCH', 'ARGUMENTS', 'TRUE', 'FALSE', 'YES', 'NO', 'ON', 'OFF', '!', '!!', 'NOT', '->', '=>', '[', '(', '{']; // The inverse mappings of token pairs we're trying to fix up. INVERSES = { }; __g = BALANCED_PAIRS; for (__h = 0; __h < __g.length; __h++) { pair = __g[__h]; INVERSES[pair[0]] = pair[1]; INVERSES[pair[1]] = pair[0]; } // 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', 'PARAM_START']; // 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 like this. re.prototype.rewrite = function rewrite(tokens) { this.tokens = tokens; this.adjust_comments(); this.remove_leading_newlines(); this.remove_mid_expression_newlines(); this.move_commas_outside_outdents(); this.close_open_calls_and_indexes(); this.add_implicit_parentheses(); this.add_implicit_indentation(); 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 the stream changes length under our feet. re.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 their own line. re.prototype.adjust_comments = function adjust_comments() { return this.scan_tokens((function(__this) { var __func = function(prev, token, post, i) { var after, before; if (!(token[0] === 'COMMENT')) { return 1; } before = this.tokens[i - 2]; after = this.tokens[i + 2]; if (before && after && ((before[0] === 'INDENT' && after[0] === 'OUTDENT') || (before[0] === 'OUTDENT' && after[0] === 'INDENT')) && before[1] === after[1]) { this.tokens.splice(i + 2, 1); this.tokens.splice(i - 2, 1); return 0; } else if (prev && prev[0] === 'TERMINATOR' && after[0] === 'INDENT') { this.tokens.splice(i + 2, 1); this.tokens[i - 1] = 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; } }; return (function() { return __func.apply(__this, arguments); }); })(this)); }; // Leading newlines would introduce an ambiguity in the grammar, so we // dispatch them here. re.prototype.remove_leading_newlines = function remove_leading_newlines() { if (this.tokens[0][0] === 'TERMINATOR') { return this.tokens.shift(); } }; // Some blocks occur in the middle of expressions -- when we're expecting // this, remove their trailing newlines. re.prototype.remove_mid_expression_newlines = function remove_mid_expression_newlines() { return this.scan_tokens((function(__this) { var __func = function(prev, token, post, i) { if (!(post && EXPRESSION_CLOSE.indexOf(post[0]) >= 0 && token[0] === 'TERMINATOR')) { return 1; } this.tokens.splice(i, 1); return 0; }; return (function() { return __func.apply(__this, arguments); }); })(this)); }; // Make sure that we don't accidentally break trailing commas, which need // to go on the outside of expression closers. re.prototype.move_commas_outside_outdents = function move_commas_outside_outdents() { return this.scan_tokens((function(__this) { var __func = function(prev, token, post, i) { if (token[0] === 'OUTDENT' && prev[0] === ',') { this.tokens.splice(i, 1, token); } return 1; }; return (function() { return __func.apply(__this, arguments); }); })(this)); }; // We've tagged the opening parenthesis of a method call, and the opening // bracket of an indexing operation. Match them with their close. re.prototype.close_open_calls_and_indexes = function close_open_calls_and_indexes() { var brackets, parens; parens = [0]; brackets = [0]; return this.scan_tokens((function(__this) { var __func = function(prev, token, post, i) { if (token[0] === 'CALL_START') { parens.push(0); } else if (token[0] === 'INDEX_START') { brackets.push(0); } else if (token[0] === '(') { parens[parens.length - 1] += 1; } else if (token[0] === '[') { brackets[brackets.length - 1] += 1; } else if (token[0] === ')') { if (parens[parens.length - 1] === 0) { parens.pop(); token[0] = 'CALL_END'; } else { parens[parens.length - 1] -= 1; } } else if (token[0] === ']') { if (brackets[brackets.length - 1] === 0) { brackets.pop(); token[0] = 'INDEX_END'; } else { brackets[brackets.length - 1] -= 1; } } return 1; }; return (function() { return __func.apply(__this, arguments); }); })(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. re.prototype.add_implicit_parentheses = function add_implicit_parentheses() { var stack; stack = [0]; return this.scan_tokens((function(__this) { var __func = function(prev, token, post, i) { var __i, __j, __k, __l, idx, last, size, tmp; if (token[0] === 'INDENT') { stack.push(0); } if (token[0] === 'OUTDENT') { last = stack.pop(); stack[stack.length - 1] += last; } if (stack[stack.length - 1] > 0 && (IMPLICIT_END.indexOf(token[0]) >= 0 || !(typeof post !== "undefined" && post !== null))) { idx = token[0] === 'OUTDENT' ? i + 1 : i; __k = 0; __l = stack[stack.length - 1]; for (__j=0, tmp=__k; (__k <= __l ? tmp < __l : tmp > __l); (__k <= __l ? tmp += 1 : tmp -= 1), __j++) { this.tokens.splice(idx, 0, ['CALL_END', ')']); } size = stack[stack.length - 1] + 1; stack[stack.length - 1] = 0; return size; } if (!(prev && IMPLICIT_FUNC.indexOf(prev[0]) >= 0 && IMPLICIT_CALL.indexOf(token[0]) >= 0)) { return 1; } this.tokens.splice(i, 0, ['CALL_START', '(']); stack[stack.length - 1] += 1; return 2; }; return (function() { return __func.apply(__this, arguments); }); })(this)); }; // Because our grammar is LALR(1), it can't handle some single-line // expressions that lack ending delimiters. Use the lexer to add the implicit // blocks, so it doesn't need to. // ')' can close a single-line block, but we need to make sure it's balanced. re.prototype.add_implicit_indentation = function add_implicit_indentation() { return this.scan_tokens((function(__this) { var __func = function(prev, token, post, i) { var idx, insertion, parens, starter, tok; if (!(SINGLE_LINERS.indexOf(token[0]) >= 0 && post[0] !== 'INDENT' && !(token[0] === 'ELSE' && post[0] === 'IF'))) { return 1; } starter = token[0]; this.tokens.splice(i + 1, 0, ['INDENT', 2]); idx = i + 1; parens = 0; while (true) { idx += 1; tok = this.tokens[idx]; if ((!tok || SINGLE_CLOSERS.indexOf(tok[0]) >= 0 || (tok[0] === ')' && parens === 0)) && !(starter === 'ELSE' && tok[0] === 'ELSE')) { insertion = this.tokens[idx - 1][0] === "," ? idx - 1 : idx; this.tokens.splice(insertion, 0, ['OUTDENT', 2]); break; } if (tok[0] === '(') { parens += 1; } if (tok[0] === ')') { parens -= 1; } } if (!(token[0] === 'THEN')) { return 1; } this.tokens.splice(i, 1); return 0; }; return (function() { return __func.apply(__this, arguments); }); })(this)); }; // Ensure that all listed pairs of tokens are correctly balanced throughout // the course of the token stream. re.prototype.ensure_balance = function ensure_balance(pairs) { var __i, __j, key, levels, unclosed, value; levels = { }; this.scan_tokens((function(__this) { var __func = function(prev, token, post, i) { var __i, __j, __k, close, open; __i = pairs; for (__j = 0; __j < __i.length; __j++) { pair = __i[__j]; __k = pair; open = __k[0]; close = __k[1]; levels[open] = levels[open] || 0; if (token[0] === open) { levels[open] += 1; } if (token[0] === close) { levels[open] -= 1; } if (levels[open] < 0) { throw "too many " + token[1]; } } return 1; }; return (function() { return __func.apply(__this, arguments); }); })(this)); unclosed = (function() { __i = []; __j = levels; for (key in __j) { value = __j[key]; if (__hasProp.call(__j, key)) { if (value > 0) { __i.push(key); } } } return __i; }).call(this); if (unclosed.length) { throw "unclosed " + unclosed[0]; } }; // 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 '(' or INDENT, add it // to the stack. If you see an ')' or OUTDENT, pop the stack and replace // it with the inverse of what we've just popped. // 3. Keep track of "debt" for tokens that we fake, to make sure we end // up balanced in the end. re.prototype.rewrite_closing_parens = function rewrite_closing_parens() { var __i, debt, key, stack, val; stack = []; debt = { }; __i = INVERSES; for (key in __i) { val = __i[key]; if (__hasProp.call(__i, key)) { ((debt[key] = 0)); } } return this.scan_tokens((function(__this) { var __func = function(prev, token, post, i) { var inv, match, mtag, tag; tag = token[0]; inv = INVERSES[token[0]]; // Push openers onto the stack. if (EXPRESSION_START.indexOf(tag) >= 0) { stack.push(token); return 1; // The end of an expression, check stack and debt for a pair. } else if (EXPRESSION_TAIL.indexOf(tag) >= 0) { // If the tag is already in our debt, swallow it. if (debt[inv] > 0) { debt[inv] -= 1; this.tokens.splice(i, 1); return 0; } else { // Pop the stack of open delimiters. match = stack.pop(); mtag = match[0]; // Continue onwards if it's the expected tag. if (tag === INVERSES[mtag]) { return 1; } else { // Unexpected close, insert correct close, adding to the debt. debt[mtag] += 1; val = mtag === 'INDENT' ? match[1] : INVERSES[mtag]; this.tokens.splice(i, 0, [INVERSES[mtag], val]); return 1; } } } else { return 1; } }; return (function() { return __func.apply(__this, arguments); }); })(this)); }; })();