1617 lines
69 KiB
JavaScript
1617 lines
69 KiB
JavaScript
/***********************************************************************
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A JavaScript tokenizer / parser / beautifier / compressor.
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This version is suitable for Node.js. With minimal changes (the
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exports stuff) it should work on any JS platform.
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This file implements some AST processors. They work on data built
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by parse-js.
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Exported functions:
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- ast_mangle(ast, options) -- mangles the variable/function names
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in the AST. Returns an AST.
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- ast_squeeze(ast) -- employs various optimizations to make the
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final generated code even smaller. Returns an AST.
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- gen_code(ast, options) -- generates JS code from the AST. Pass
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true (or an object, see the code for some options) as second
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argument to get "pretty" (indented) code.
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-------------------------------- (C) ---------------------------------
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Author: Mihai Bazon
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<mihai.bazon@gmail.com>
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http://mihai.bazon.net/blog
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Distributed under the BSD license:
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Copyright 2010 (c) Mihai Bazon <mihai.bazon@gmail.com>
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Redistribution and use in source and binary forms, with or without
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modification, are permitted provided that the following conditions
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are met:
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* Redistributions of source code must retain the above
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copyright notice, this list of conditions and the following
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disclaimer.
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* Redistributions in binary form must reproduce the above
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copyright notice, this list of conditions and the following
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disclaimer in the documentation and/or other materials
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provided with the distribution.
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THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDER “AS IS” AND ANY
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EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
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IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
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PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER BE
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LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY,
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OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
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PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
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PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
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THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR
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TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF
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THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
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SUCH DAMAGE.
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***********************************************************************/
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var jsp = require("./parse-js"),
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slice = jsp.slice,
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member = jsp.member,
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PRECEDENCE = jsp.PRECEDENCE,
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OPERATORS = jsp.OPERATORS;
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/* -----[ helper for AST traversal ]----- */
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function ast_walker(ast) {
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function _vardefs(defs) {
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return [ this[0], MAP(defs, function(def){
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var a = [ def[0] ];
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if (def.length > 1)
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a[1] = walk(def[1]);
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return a;
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}) ];
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};
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var walkers = {
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"string": function(str) {
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return [ this[0], str ];
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},
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"num": function(num) {
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return [ this[0], num ];
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},
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"name": function(name) {
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return [ this[0], name ];
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},
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"toplevel": function(statements) {
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return [ this[0], MAP(statements, walk) ];
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},
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"block": function(statements) {
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var out = [ this[0] ];
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if (statements != null)
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out.push(MAP(statements, walk));
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return out;
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},
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"var": _vardefs,
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"const": _vardefs,
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"try": function(t, c, f) {
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return [
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this[0],
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MAP(t, walk),
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c != null ? [ c[0], MAP(c[1], walk) ] : null,
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f != null ? MAP(f, walk) : null
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];
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},
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"throw": function(expr) {
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return [ this[0], walk(expr) ];
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},
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"new": function(ctor, args) {
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return [ this[0], walk(ctor), MAP(args, walk) ];
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},
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"switch": function(expr, body) {
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return [ this[0], walk(expr), MAP(body, function(branch){
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return [ branch[0] ? walk(branch[0]) : null,
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MAP(branch[1], walk) ];
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}) ];
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},
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"break": function(label) {
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return [ this[0], label ];
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},
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"continue": function(label) {
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return [ this[0], label ];
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},
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"conditional": function(cond, t, e) {
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return [ this[0], walk(cond), walk(t), walk(e) ];
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},
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"assign": function(op, lvalue, rvalue) {
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return [ this[0], op, walk(lvalue), walk(rvalue) ];
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},
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"dot": function(expr) {
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return [ this[0], walk(expr) ].concat(slice(arguments, 1));
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},
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"call": function(expr, args) {
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return [ this[0], walk(expr), MAP(args, walk) ];
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},
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"function": function(name, args, body) {
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return [ this[0], name, args.slice(), MAP(body, walk) ];
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},
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"defun": function(name, args, body) {
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return [ this[0], name, args.slice(), MAP(body, walk) ];
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},
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"if": function(conditional, t, e) {
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return [ this[0], walk(conditional), walk(t), walk(e) ];
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},
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"for": function(init, cond, step, block) {
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return [ this[0], walk(init), walk(cond), walk(step), walk(block) ];
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},
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"for-in": function(vvar, key, hash, block) {
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return [ this[0], walk(vvar), walk(key), walk(hash), walk(block) ];
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},
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"while": function(cond, block) {
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return [ this[0], walk(cond), walk(block) ];
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},
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"do": function(cond, block) {
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return [ this[0], walk(cond), walk(block) ];
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},
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"return": function(expr) {
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return [ this[0], walk(expr) ];
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},
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"binary": function(op, left, right) {
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return [ this[0], op, walk(left), walk(right) ];
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},
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"unary-prefix": function(op, expr) {
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return [ this[0], op, walk(expr) ];
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},
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"unary-postfix": function(op, expr) {
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return [ this[0], op, walk(expr) ];
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},
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"sub": function(expr, subscript) {
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return [ this[0], walk(expr), walk(subscript) ];
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},
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"object": function(props) {
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return [ this[0], MAP(props, function(p){
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return p.length == 2
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? [ p[0], walk(p[1]) ]
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: [ p[0], walk(p[1]), p[2] ]; // get/set-ter
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}) ];
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},
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"regexp": function(rx, mods) {
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return [ this[0], rx, mods ];
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},
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"array": function(elements) {
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return [ this[0], MAP(elements, walk) ];
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},
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"stat": function(stat) {
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return [ this[0], walk(stat) ];
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},
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"seq": function() {
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return [ this[0] ].concat(MAP(slice(arguments), walk));
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},
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"label": function(name, block) {
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return [ this[0], name, walk(block) ];
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},
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"with": function(expr, block) {
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return [ this[0], walk(expr), walk(block) ];
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},
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"atom": function(name) {
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return [ this[0], name ];
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}
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};
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var user = {};
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var stack = [];
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function walk(ast) {
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if (ast == null)
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return null;
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try {
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stack.push(ast);
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var type = ast[0];
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var gen = user[type];
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if (gen) {
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var ret = gen.apply(ast, ast.slice(1));
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if (ret != null)
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return ret;
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}
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gen = walkers[type];
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return gen.apply(ast, ast.slice(1));
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} finally {
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stack.pop();
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}
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};
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function with_walkers(walkers, cont){
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var save = {}, i;
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for (i in walkers) if (HOP(walkers, i)) {
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save[i] = user[i];
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user[i] = walkers[i];
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}
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var ret = cont();
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for (i in save) if (HOP(save, i)) {
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if (!save[i]) delete user[i];
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else user[i] = save[i];
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}
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return ret;
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};
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return {
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walk: walk,
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with_walkers: with_walkers,
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parent: function() {
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return stack[stack.length - 2]; // last one is current node
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},
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stack: function() {
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return stack;
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}
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};
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};
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/* -----[ Scope and mangling ]----- */
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function Scope(parent) {
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this.names = {}; // names defined in this scope
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this.mangled = {}; // mangled names (orig.name => mangled)
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this.rev_mangled = {}; // reverse lookup (mangled => orig.name)
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this.cname = -1; // current mangled name
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this.refs = {}; // names referenced from this scope
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this.uses_with = false; // will become TRUE if with() is detected in this or any subscopes
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this.uses_eval = false; // will become TRUE if eval() is detected in this or any subscopes
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this.parent = parent; // parent scope
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this.children = []; // sub-scopes
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if (parent) {
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this.level = parent.level + 1;
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parent.children.push(this);
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} else {
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this.level = 0;
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}
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};
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var base54 = (function(){
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var DIGITS = "abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ$_";
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return function(num) {
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var ret = "";
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do {
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ret = DIGITS.charAt(num % 54) + ret;
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num = Math.floor(num / 54);
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} while (num > 0);
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return ret;
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};
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})();
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Scope.prototype = {
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has: function(name) {
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for (var s = this; s; s = s.parent)
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if (HOP(s.names, name))
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return s;
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},
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has_mangled: function(mname) {
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for (var s = this; s; s = s.parent)
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if (HOP(s.rev_mangled, mname))
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return s;
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},
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toJSON: function() {
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return {
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names: this.names,
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uses_eval: this.uses_eval,
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uses_with: this.uses_with
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};
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},
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next_mangled: function() {
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// we must be careful that the new mangled name:
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//
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// 1. doesn't shadow a mangled name from a parent
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// scope, unless we don't reference the original
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// name from this scope OR from any sub-scopes!
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// This will get slow.
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//
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// 2. doesn't shadow an original name from a parent
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// scope, in the event that the name is not mangled
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// in the parent scope and we reference that name
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// here OR IN ANY SUBSCOPES!
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//
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// 3. doesn't shadow a name that is referenced but not
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// defined (possibly global defined elsewhere).
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for (;;) {
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var m = base54(++this.cname), prior;
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// case 1.
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prior = this.has_mangled(m);
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if (prior && this.refs[prior.rev_mangled[m]] === prior)
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continue;
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// case 2.
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prior = this.has(m);
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if (prior && prior !== this && this.refs[m] === prior && !prior.has_mangled(m))
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continue;
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// case 3.
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if (HOP(this.refs, m) && this.refs[m] == null)
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continue;
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// I got "do" once. :-/
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if (!is_identifier(m))
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continue;
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return m;
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}
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},
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get_mangled: function(name, newMangle) {
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if (this.uses_eval || this.uses_with) return name; // no mangle if eval or with is in use
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var s = this.has(name);
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if (!s) return name; // not in visible scope, no mangle
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if (HOP(s.mangled, name)) return s.mangled[name]; // already mangled in this scope
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if (!newMangle) return name; // not found and no mangling requested
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var m = s.next_mangled();
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s.rev_mangled[m] = name;
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return s.mangled[name] = m;
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},
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define: function(name) {
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if (name != null)
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return this.names[name] = name;
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}
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};
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function ast_add_scope(ast) {
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var current_scope = null;
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var w = ast_walker(), walk = w.walk;
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var having_eval = [];
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function with_new_scope(cont) {
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current_scope = new Scope(current_scope);
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var ret = current_scope.body = cont();
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ret.scope = current_scope;
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current_scope = current_scope.parent;
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return ret;
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};
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function define(name) {
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return current_scope.define(name);
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};
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function reference(name) {
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current_scope.refs[name] = true;
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};
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function _lambda(name, args, body) {
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return [ this[0], this[0] == "defun" ? define(name) : name, args, with_new_scope(function(){
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MAP(args, define);
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return MAP(body, walk);
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})];
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};
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return with_new_scope(function(){
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// process AST
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var ret = w.with_walkers({
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"function": _lambda,
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"defun": _lambda,
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"with": function(expr, block) {
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for (var s = current_scope; s; s = s.parent)
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s.uses_with = true;
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},
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"var": function(defs) {
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MAP(defs, function(d){ define(d[0]) });
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},
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"const": function(defs) {
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MAP(defs, function(d){ define(d[0]) });
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},
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"try": function(t, c, f) {
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if (c != null) return [
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this[0],
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MAP(t, walk),
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[ define(c[0]), MAP(c[1], walk) ],
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f != null ? MAP(f, walk) : null
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];
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},
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"name": function(name) {
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if (name == "eval")
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having_eval.push(current_scope);
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reference(name);
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}
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}, function(){
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return walk(ast);
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});
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// the reason why we need an additional pass here is
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// that names can be used prior to their definition.
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// scopes where eval was detected and their parents
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// are marked with uses_eval, unless they define the
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// "eval" name.
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MAP(having_eval, function(scope){
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if (!scope.has("eval")) while (scope) {
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scope.uses_eval = true;
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scope = scope.parent;
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}
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});
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// for referenced names it might be useful to know
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// their origin scope. current_scope here is the
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// toplevel one.
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function fixrefs(scope, i) {
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// do children first; order shouldn't matter
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for (i = scope.children.length; --i >= 0;)
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fixrefs(scope.children[i]);
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for (i in scope.refs) if (HOP(scope.refs, i)) {
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// find origin scope and propagate the reference to origin
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for (var origin = scope.has(i), s = scope; s; s = s.parent) {
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s.refs[i] = origin;
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if (s === origin) break;
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}
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}
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};
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fixrefs(current_scope);
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return ret;
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});
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};
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/* -----[ mangle names ]----- */
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function ast_mangle(ast, options) {
|
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var w = ast_walker(), walk = w.walk, scope;
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options = options || {};
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function get_mangled(name, newMangle) {
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if (!options.toplevel && !scope.parent) return name; // don't mangle toplevel
|
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if (options.except && member(name, options.except))
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return name;
|
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return scope.get_mangled(name, newMangle);
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};
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|
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function _lambda(name, args, body) {
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if (name) name = get_mangled(name);
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body = with_scope(body.scope, function(){
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args = MAP(args, function(name){ return get_mangled(name) });
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return MAP(body, walk);
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});
|
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return [ this[0], name, args, body ];
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};
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|
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function with_scope(s, cont) {
|
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var _scope = scope;
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scope = s;
|
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for (var i in s.names) if (HOP(s.names, i)) {
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get_mangled(i, true);
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}
|
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var ret = cont();
|
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ret.scope = s;
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scope = _scope;
|
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return ret;
|
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};
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|
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function _vardefs(defs) {
|
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return [ this[0], MAP(defs, function(d){
|
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return [ get_mangled(d[0]), walk(d[1]) ];
|
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}) ];
|
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};
|
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|
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return w.with_walkers({
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"function": _lambda,
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"defun": function() {
|
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// move function declarations to the top when
|
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// they are not in some block.
|
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var ast = _lambda.apply(this, arguments);
|
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switch (w.parent()[0]) {
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case "toplevel":
|
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case "function":
|
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case "defun":
|
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return MAP.at_top(ast);
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}
|
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return ast;
|
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},
|
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"var": _vardefs,
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"const": _vardefs,
|
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"name": function(name) {
|
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return [ this[0], get_mangled(name) ];
|
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},
|
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"try": function(t, c, f) {
|
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return [ this[0],
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MAP(t, walk),
|
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c != null ? [ get_mangled(c[0]), MAP(c[1], walk) ] : null,
|
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f != null ? MAP(f, walk) : null ];
|
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},
|
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"toplevel": function(body) {
|
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var self = this;
|
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return with_scope(self.scope, function(){
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return [ self[0], MAP(body, walk) ];
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});
|
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}
|
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}, function() {
|
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return walk(ast_add_scope(ast));
|
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});
|
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};
|
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|
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/* -----[
|
|
- compress foo["bar"] into foo.bar,
|
|
- remove block brackets {} where possible
|
|
- join consecutive var declarations
|
|
- various optimizations for IFs:
|
|
- if (cond) foo(); else bar(); ==> cond?foo():bar();
|
|
- if (cond) foo(); ==> cond&&foo();
|
|
- if (foo) return bar(); else return baz(); ==> return foo?bar():baz(); // also for throw
|
|
- if (foo) return bar(); else something(); ==> {if(foo)return bar();something()}
|
|
]----- */
|
|
|
|
var warn = function(){};
|
|
|
|
function best_of(ast1, ast2) {
|
|
return gen_code(ast1).length > gen_code(ast2[0] == "stat" ? ast2[1] : ast2).length ? ast2 : ast1;
|
|
};
|
|
|
|
function last_stat(b) {
|
|
if (b[0] == "block" && b[1] && b[1].length > 0)
|
|
return b[1][b[1].length - 1];
|
|
return b;
|
|
}
|
|
|
|
function aborts(t) {
|
|
if (t) {
|
|
t = last_stat(t);
|
|
if (t[0] == "return" || t[0] == "break" || t[0] == "continue" || t[0] == "throw")
|
|
return true;
|
|
}
|
|
};
|
|
|
|
function boolean_expr(expr) {
|
|
return ( (expr[0] == "unary-prefix"
|
|
&& member(expr[1], [ "!", "delete" ])) ||
|
|
|
|
(expr[0] == "binary"
|
|
&& member(expr[1], [ "in", "instanceof", "==", "!=", "===", "!==", "<", "<=", ">=", ">" ])) ||
|
|
|
|
(expr[0] == "binary"
|
|
&& member(expr[1], [ "&&", "||" ])
|
|
&& boolean_expr(expr[2])
|
|
&& boolean_expr(expr[3])) ||
|
|
|
|
(expr[0] == "conditional"
|
|
&& boolean_expr(expr[2])
|
|
&& boolean_expr(expr[3])) ||
|
|
|
|
(expr[0] == "assign"
|
|
&& expr[1] === true
|
|
&& boolean_expr(expr[3])) ||
|
|
|
|
(expr[0] == "seq"
|
|
&& boolean_expr(expr[expr.length - 1]))
|
|
);
|
|
};
|
|
|
|
function make_conditional(c, t, e) {
|
|
if (c[0] == "unary-prefix" && c[1] == "!") {
|
|
return e ? [ "conditional", c[2], e, t ] : [ "binary", "||", c[2], t ];
|
|
} else {
|
|
return e ? [ "conditional", c, t, e ] : [ "binary", "&&", c, t ];
|
|
}
|
|
};
|
|
|
|
function empty(b) {
|
|
return !b || (b[0] == "block" && (!b[1] || b[1].length == 0));
|
|
};
|
|
|
|
function is_string(node) {
|
|
return (node[0] == "string" ||
|
|
node[0] == "unary-prefix" && node[1] == "typeof" ||
|
|
node[0] == "binary" && node[1] == "+" &&
|
|
(is_string(node[2]) || is_string(node[3])));
|
|
};
|
|
|
|
var when_constant = (function(){
|
|
|
|
var $NOT_CONSTANT = {};
|
|
|
|
// this can only evaluate constant expressions. If it finds anything
|
|
// not constant, it throws $NOT_CONSTANT.
|
|
function evaluate(expr) {
|
|
switch (expr[0]) {
|
|
case "string":
|
|
case "num":
|
|
return expr[1];
|
|
case "name":
|
|
case "atom":
|
|
switch (expr[1]) {
|
|
case "true": return true;
|
|
case "false": return false;
|
|
}
|
|
break;
|
|
case "unary-prefix":
|
|
switch (expr[1]) {
|
|
case "!": return !evaluate(expr[2]);
|
|
case "typeof": return typeof evaluate(expr[2]);
|
|
case "~": return ~evaluate(expr[2]);
|
|
case "-": return -evaluate(expr[2]);
|
|
case "+": return +evaluate(expr[2]);
|
|
}
|
|
break;
|
|
case "binary":
|
|
var left = expr[2], right = expr[3];
|
|
switch (expr[1]) {
|
|
case "&&" : return evaluate(left) && evaluate(right);
|
|
case "||" : return evaluate(left) || evaluate(right);
|
|
case "|" : return evaluate(left) | evaluate(right);
|
|
case "&" : return evaluate(left) & evaluate(right);
|
|
case "^" : return evaluate(left) ^ evaluate(right);
|
|
case "+" : return evaluate(left) + evaluate(right);
|
|
case "*" : return evaluate(left) * evaluate(right);
|
|
case "/" : return evaluate(left) / evaluate(right);
|
|
case "-" : return evaluate(left) - evaluate(right);
|
|
case "<<" : return evaluate(left) << evaluate(right);
|
|
case ">>" : return evaluate(left) >> evaluate(right);
|
|
case ">>>" : return evaluate(left) >>> evaluate(right);
|
|
case "==" : return evaluate(left) == evaluate(right);
|
|
case "===" : return evaluate(left) === evaluate(right);
|
|
case "!=" : return evaluate(left) != evaluate(right);
|
|
case "!==" : return evaluate(left) !== evaluate(right);
|
|
case "<" : return evaluate(left) < evaluate(right);
|
|
case "<=" : return evaluate(left) <= evaluate(right);
|
|
case ">" : return evaluate(left) > evaluate(right);
|
|
case ">=" : return evaluate(left) >= evaluate(right);
|
|
case "in" : return evaluate(left) in evaluate(right);
|
|
case "instanceof" : return evaluate(left) instanceof evaluate(right);
|
|
}
|
|
}
|
|
throw $NOT_CONSTANT;
|
|
};
|
|
|
|
return function(expr, yes, no) {
|
|
try {
|
|
var val = evaluate(expr), ast;
|
|
switch (typeof val) {
|
|
case "string": ast = [ "string", val ]; break;
|
|
case "number": ast = [ "num", val ]; break;
|
|
case "boolean": ast = [ "name", String(val) ]; break;
|
|
default: throw new Error("Can't handle constant of type: " + (typeof val));
|
|
}
|
|
return yes.call(expr, ast, val);
|
|
} catch(ex) {
|
|
if (ex === $NOT_CONSTANT) {
|
|
if (expr[0] == "binary"
|
|
&& (expr[1] == "===" || expr[1] == "!==")
|
|
&& ((is_string(expr[2]) && is_string(expr[3]))
|
|
|| (boolean_expr(expr[2]) && boolean_expr(expr[3])))) {
|
|
expr[1] = expr[1].substr(0, 2);
|
|
}
|
|
return no ? no.call(expr, expr) : null;
|
|
}
|
|
else throw ex;
|
|
}
|
|
};
|
|
|
|
})();
|
|
|
|
function warn_unreachable(ast) {
|
|
if (!empty(ast))
|
|
warn("Dropping unreachable code: " + gen_code(ast, true));
|
|
};
|
|
|
|
function ast_squeeze(ast, options) {
|
|
options = defaults(options, {
|
|
make_seqs : true,
|
|
dead_code : true,
|
|
keep_comps : true,
|
|
no_warnings : false
|
|
});
|
|
|
|
var w = ast_walker(), walk = w.walk, scope;
|
|
|
|
function negate(c) {
|
|
var not_c = [ "unary-prefix", "!", c ];
|
|
switch (c[0]) {
|
|
case "unary-prefix":
|
|
return c[1] == "!" && boolean_expr(c[2]) ? c[2] : not_c;
|
|
case "seq":
|
|
c = slice(c);
|
|
c[c.length - 1] = negate(c[c.length - 1]);
|
|
return c;
|
|
case "conditional":
|
|
return best_of(not_c, [ "conditional", c[1], negate(c[2]), negate(c[3]) ]);
|
|
case "binary":
|
|
var op = c[1], left = c[2], right = c[3];
|
|
if (!options.keep_comps) switch (op) {
|
|
case "<=" : return [ "binary", ">", left, right ];
|
|
case "<" : return [ "binary", ">=", left, right ];
|
|
case ">=" : return [ "binary", "<", left, right ];
|
|
case ">" : return [ "binary", "<=", left, right ];
|
|
}
|
|
switch (op) {
|
|
case "==" : return [ "binary", "!=", left, right ];
|
|
case "!=" : return [ "binary", "==", left, right ];
|
|
case "===" : return [ "binary", "!==", left, right ];
|
|
case "!==" : return [ "binary", "===", left, right ];
|
|
case "&&" : return best_of(not_c, [ "binary", "||", negate(left), negate(right) ]);
|
|
case "||" : return best_of(not_c, [ "binary", "&&", negate(left), negate(right) ]);
|
|
}
|
|
break;
|
|
}
|
|
return not_c;
|
|
};
|
|
|
|
function with_scope(s, cont) {
|
|
var _scope = scope;
|
|
scope = s;
|
|
var ret = cont();
|
|
ret.scope = s;
|
|
scope = _scope;
|
|
return ret;
|
|
};
|
|
|
|
function rmblock(block) {
|
|
if (block != null && block[0] == "block" && block[1]) {
|
|
if (block[1].length == 1)
|
|
block = block[1][0];
|
|
else if (block[1].length == 0)
|
|
block = [ "block" ];
|
|
}
|
|
return block;
|
|
};
|
|
|
|
function _lambda(name, args, body) {
|
|
return [ this[0], name, args, with_scope(body.scope, function(){
|
|
return tighten(MAP(body, walk), "lambda");
|
|
}) ];
|
|
};
|
|
|
|
// we get here for blocks that have been already transformed.
|
|
// this function does a few things:
|
|
// 1. discard useless blocks
|
|
// 2. join consecutive var declarations
|
|
// 3. remove obviously dead code
|
|
// 4. transform consecutive statements using the comma operator
|
|
// 5. if block_type == "lambda" and it detects constructs like if(foo) return ... - rewrite like if (!foo) { ... }
|
|
function tighten(statements, block_type) {
|
|
statements = statements.reduce(function(a, stat){
|
|
if (stat[0] == "block") {
|
|
if (stat[1]) {
|
|
a.push.apply(a, stat[1]);
|
|
}
|
|
} else {
|
|
a.push(stat);
|
|
}
|
|
return a;
|
|
}, []);
|
|
|
|
statements = (function(a, prev){
|
|
statements.forEach(function(cur){
|
|
if (prev && ((cur[0] == "var" && prev[0] == "var") ||
|
|
(cur[0] == "const" && prev[0] == "const"))) {
|
|
prev[1] = prev[1].concat(cur[1]);
|
|
} else {
|
|
a.push(cur);
|
|
prev = cur;
|
|
}
|
|
});
|
|
return a;
|
|
})([]);
|
|
|
|
if (options.dead_code) statements = (function(a, has_quit){
|
|
statements.forEach(function(st){
|
|
if (has_quit) {
|
|
if (member(st[0], [ "function", "defun" , "var", "const" ])) {
|
|
a.push(st);
|
|
}
|
|
else if (!options.no_warnings)
|
|
warn_unreachable(st);
|
|
}
|
|
else {
|
|
a.push(st);
|
|
if (member(st[0], [ "return", "throw", "break", "continue" ]))
|
|
has_quit = true;
|
|
}
|
|
});
|
|
return a;
|
|
})([]);
|
|
|
|
if (options.make_seqs) statements = (function(a, prev) {
|
|
statements.forEach(function(cur){
|
|
if (prev && prev[0] == "stat" && cur[0] == "stat") {
|
|
prev[1] = [ "seq", prev[1], cur[1] ];
|
|
} else {
|
|
a.push(cur);
|
|
prev = cur;
|
|
}
|
|
});
|
|
return a;
|
|
})([]);
|
|
|
|
if (block_type == "lambda") statements = (function(i, a, stat){
|
|
while (i < statements.length) {
|
|
stat = statements[i++];
|
|
if (stat[0] == "if" && !stat[3]) {
|
|
if (stat[2][0] == "return" && stat[2][1] == null) {
|
|
a.push(make_if(negate(stat[1]), [ "block", statements.slice(i) ]));
|
|
break;
|
|
}
|
|
var last = last_stat(stat[2]);
|
|
if (last[0] == "return" && last[1] == null) {
|
|
a.push(make_if(stat[1], [ "block", stat[2][1].slice(0, -1) ], [ "block", statements.slice(i) ]));
|
|
break;
|
|
}
|
|
}
|
|
a.push(stat);
|
|
}
|
|
return a;
|
|
})(0, []);
|
|
|
|
return statements;
|
|
};
|
|
|
|
function make_if(c, t, e) {
|
|
return when_constant(c, function(ast, val){
|
|
if (val) {
|
|
warn_unreachable(e);
|
|
return t;
|
|
} else {
|
|
warn_unreachable(t);
|
|
return e;
|
|
}
|
|
}, function() {
|
|
return make_real_if(c, t, e);
|
|
});
|
|
};
|
|
|
|
function make_real_if(c, t, e) {
|
|
c = walk(c);
|
|
t = walk(t);
|
|
e = walk(e);
|
|
|
|
if (empty(t)) {
|
|
c = negate(c);
|
|
t = e;
|
|
e = null;
|
|
} else if (empty(e)) {
|
|
e = null;
|
|
} else {
|
|
// if we have both else and then, maybe it makes sense to switch them?
|
|
(function(){
|
|
var a = gen_code(c);
|
|
var n = negate(c);
|
|
var b = gen_code(n);
|
|
if (b.length < a.length) {
|
|
var tmp = t;
|
|
t = e;
|
|
e = tmp;
|
|
c = n;
|
|
}
|
|
})();
|
|
}
|
|
if (empty(e) && empty(t))
|
|
return [ "stat", c ];
|
|
var ret = [ "if", c, t, e ];
|
|
if (t[0] == "if" && empty(t[3]) && empty(e)) {
|
|
ret = best_of(ret, walk([ "if", [ "binary", "&&", c, t[1] ], t[2] ]));
|
|
}
|
|
else if (t[0] == "stat") {
|
|
if (e) {
|
|
if (e[0] == "stat") {
|
|
ret = best_of(ret, [ "stat", make_conditional(c, t[1], e[1]) ]);
|
|
}
|
|
}
|
|
else {
|
|
ret = best_of(ret, [ "stat", make_conditional(c, t[1]) ]);
|
|
}
|
|
}
|
|
else if (e && t[0] == e[0] && (t[0] == "return" || t[0] == "throw") && t[1] && e[1]) {
|
|
ret = best_of(ret, [ t[0], make_conditional(c, t[1], e[1] ) ]);
|
|
}
|
|
else if (e && aborts(t)) {
|
|
ret = [ [ "if", c, t ] ];
|
|
if (e[0] == "block") {
|
|
if (e[1]) ret = ret.concat(e[1]);
|
|
}
|
|
else {
|
|
ret.push(e);
|
|
}
|
|
ret = walk([ "block", ret ]);
|
|
}
|
|
else if (t && aborts(e)) {
|
|
ret = [ [ "if", negate(c), e ] ];
|
|
if (t[0] == "block") {
|
|
if (t[1]) ret = ret.concat(t[1]);
|
|
} else {
|
|
ret.push(t);
|
|
}
|
|
ret = walk([ "block", ret ]);
|
|
}
|
|
return ret;
|
|
};
|
|
|
|
function _do_while(cond, body) {
|
|
return when_constant(cond, function(cond, val){
|
|
if (!val) {
|
|
warn_unreachable(body);
|
|
return [ "block" ];
|
|
} else {
|
|
return [ "for", null, null, null, walk(body) ];
|
|
}
|
|
});
|
|
};
|
|
|
|
return w.with_walkers({
|
|
"sub": function(expr, subscript) {
|
|
if (subscript[0] == "string") {
|
|
var name = subscript[1];
|
|
if (is_identifier(name))
|
|
return [ "dot", walk(expr), name ];
|
|
else if (/^[1-9][0-9]*$/.test(name) || name === "0")
|
|
return [ "sub", walk(expr), [ "num", parseInt(name, 10) ] ];
|
|
}
|
|
},
|
|
"if": make_if,
|
|
"toplevel": function(body) {
|
|
return [ "toplevel", with_scope(this.scope, function(){
|
|
return tighten(MAP(body, walk));
|
|
}) ];
|
|
},
|
|
"switch": function(expr, body) {
|
|
var last = body.length - 1;
|
|
return [ "switch", walk(expr), MAP(body, function(branch, i){
|
|
var block = tighten(MAP(branch[1], walk));
|
|
if (i == last && block.length > 0) {
|
|
var node = block[block.length - 1];
|
|
if (node[0] == "break" && !node[1])
|
|
block.pop();
|
|
}
|
|
return [ branch[0] ? walk(branch[0]) : null, block ];
|
|
}) ];
|
|
},
|
|
"function": function() {
|
|
var ret = _lambda.apply(this, arguments);
|
|
if (ret[1] && !HOP(scope.refs, ret[1])) {
|
|
ret[1] = null;
|
|
}
|
|
return ret;
|
|
},
|
|
"defun": _lambda,
|
|
"block": function(body) {
|
|
if (body) return rmblock([ "block", tighten(MAP(body, walk)) ]);
|
|
},
|
|
"binary": function(op, left, right) {
|
|
return when_constant([ "binary", op, walk(left), walk(right) ], function yes(c){
|
|
return best_of(walk(c), this);
|
|
}, function no() {
|
|
return this;
|
|
});
|
|
},
|
|
"conditional": function(c, t, e) {
|
|
return make_conditional(walk(c), walk(t), walk(e));
|
|
},
|
|
"try": function(t, c, f) {
|
|
return [
|
|
"try",
|
|
tighten(MAP(t, walk)),
|
|
c != null ? [ c[0], tighten(MAP(c[1], walk)) ] : null,
|
|
f != null ? tighten(MAP(f, walk)) : null
|
|
];
|
|
},
|
|
"unary-prefix": function(op, expr) {
|
|
expr = walk(expr);
|
|
var ret = [ "unary-prefix", op, expr ];
|
|
if (op == "!")
|
|
ret = best_of(ret, negate(expr));
|
|
return when_constant(ret, function(ast, val){
|
|
return walk(ast); // it's either true or false, so minifies to !0 or !1
|
|
}, function() { return ret });
|
|
},
|
|
"name": function(name) {
|
|
switch (name) {
|
|
case "true": return [ "unary-prefix", "!", [ "num", 0 ]];
|
|
case "false": return [ "unary-prefix", "!", [ "num", 1 ]];
|
|
}
|
|
},
|
|
"new": function(ctor, args) {
|
|
if (ctor[0] == "name" && ctor[1] == "Array" && !scope.has("Array")) {
|
|
if (args.length != 1) {
|
|
return [ "array", args ];
|
|
} else {
|
|
return [ "call", [ "name", "Array" ], args ];
|
|
}
|
|
}
|
|
},
|
|
"call": function(expr, args) {
|
|
if (expr[0] == "name" && expr[1] == "Array" && args.length != 1 && !scope.has("Array")) {
|
|
return [ "array", args ];
|
|
}
|
|
},
|
|
"while": _do_while,
|
|
"do": _do_while
|
|
}, function() {
|
|
return walk(ast_add_scope(ast));
|
|
});
|
|
};
|
|
|
|
/* -----[ re-generate code from the AST ]----- */
|
|
|
|
var DOT_CALL_NO_PARENS = jsp.array_to_hash([
|
|
"name",
|
|
"array",
|
|
"object",
|
|
"string",
|
|
"dot",
|
|
"sub",
|
|
"call",
|
|
"regexp"
|
|
]);
|
|
|
|
function make_string(str, ascii_only) {
|
|
var dq = 0, sq = 0;
|
|
str = str.replace(/[\\\b\f\n\r\t\x22\x27\u2028\u2029]/g, function(s){
|
|
switch (s) {
|
|
case "\\": return "\\\\";
|
|
case "\b": return "\\b";
|
|
case "\f": return "\\f";
|
|
case "\n": return "\\n";
|
|
case "\r": return "\\r";
|
|
case "\t": return "\\t";
|
|
case "\u2028": return "\\u2028";
|
|
case "\u2029": return "\\u2029";
|
|
case '"': ++dq; return '"';
|
|
case "'": ++sq; return "'";
|
|
}
|
|
return s;
|
|
});
|
|
if (ascii_only) str = to_ascii(str);
|
|
if (dq > sq) return "'" + str.replace(/\x27/g, "\\'") + "'";
|
|
else return '"' + str.replace(/\x22/g, '\\"') + '"';
|
|
};
|
|
|
|
function to_ascii(str) {
|
|
return str.replace(/[\u0080-\uffff]/g, function(ch) {
|
|
var code = ch.charCodeAt(0).toString(16);
|
|
while (code.length < 4) code = "0" + code;
|
|
return "\\u" + code;
|
|
});
|
|
};
|
|
|
|
function gen_code(ast, options) {
|
|
options = defaults(options, {
|
|
indent_start : 0,
|
|
indent_level : 4,
|
|
quote_keys : false,
|
|
space_colon : false,
|
|
beautify : false,
|
|
ascii_only : false
|
|
});
|
|
var beautify = !!options.beautify;
|
|
var indentation = 0,
|
|
newline = beautify ? "\n" : "",
|
|
space = beautify ? " " : "";
|
|
|
|
function encode_string(str) {
|
|
return make_string(str, options.ascii_only);
|
|
};
|
|
|
|
function make_name(name) {
|
|
name = name.toString();
|
|
if (options.ascii_only)
|
|
name = to_ascii(name);
|
|
return name;
|
|
};
|
|
|
|
function indent(line) {
|
|
if (line == null)
|
|
line = "";
|
|
if (beautify)
|
|
line = repeat_string(" ", options.indent_start + indentation * options.indent_level) + line;
|
|
return line;
|
|
};
|
|
|
|
function with_indent(cont, incr) {
|
|
if (incr == null) incr = 1;
|
|
indentation += incr;
|
|
try { return cont.apply(null, slice(arguments, 1)); }
|
|
finally { indentation -= incr; }
|
|
};
|
|
|
|
function add_spaces(a) {
|
|
if (beautify)
|
|
return a.join(" ");
|
|
var b = [];
|
|
for (var i = 0; i < a.length; ++i) {
|
|
var next = a[i + 1];
|
|
b.push(a[i]);
|
|
if (next &&
|
|
((/[a-z0-9_\x24]$/i.test(a[i].toString()) && /^[a-z0-9_\x24]/i.test(next.toString())) ||
|
|
(/[\+\-]$/.test(a[i].toString()) && /^[\+\-]/.test(next.toString())))) {
|
|
b.push(" ");
|
|
}
|
|
}
|
|
return b.join("");
|
|
};
|
|
|
|
function add_commas(a) {
|
|
return a.join("," + space);
|
|
};
|
|
|
|
function parenthesize(expr) {
|
|
var gen = make(expr);
|
|
for (var i = 1; i < arguments.length; ++i) {
|
|
var el = arguments[i];
|
|
if ((el instanceof Function && el(expr)) || expr[0] == el)
|
|
return "(" + gen + ")";
|
|
}
|
|
return gen;
|
|
};
|
|
|
|
function best_of(a) {
|
|
if (a.length == 1) {
|
|
return a[0];
|
|
}
|
|
if (a.length == 2) {
|
|
var b = a[1];
|
|
a = a[0];
|
|
return a.length <= b.length ? a : b;
|
|
}
|
|
return best_of([ a[0], best_of(a.slice(1)) ]);
|
|
};
|
|
|
|
function needs_parens(expr) {
|
|
if (expr[0] == "function" || expr[0] == "object") {
|
|
// dot/call on a literal function requires the
|
|
// function literal itself to be parenthesized
|
|
// only if it's the first "thing" in a
|
|
// statement. This means that the parent is
|
|
// "stat", but it could also be a "seq" and
|
|
// we're the first in this "seq" and the
|
|
// parent is "stat", and so on. Messy stuff,
|
|
// but it worths the trouble.
|
|
var a = slice($stack), self = a.pop(), p = a.pop();
|
|
while (p) {
|
|
if (p[0] == "stat") return true;
|
|
if (((p[0] == "seq" || p[0] == "call" || p[0] == "dot" || p[0] == "sub" || p[0] == "conditional") && p[1] === self) ||
|
|
((p[0] == "binary" || p[0] == "assign" || p[0] == "unary-postfix") && p[2] === self)) {
|
|
self = p;
|
|
p = a.pop();
|
|
} else {
|
|
return false;
|
|
}
|
|
}
|
|
}
|
|
return !HOP(DOT_CALL_NO_PARENS, expr[0]);
|
|
};
|
|
|
|
function make_num(num) {
|
|
var str = num.toString(10), a = [ str.replace(/^0\./, ".") ], m;
|
|
if (Math.floor(num) === num) {
|
|
a.push("0x" + num.toString(16).toLowerCase(), // probably pointless
|
|
"0" + num.toString(8)); // same.
|
|
if ((m = /^(.*?)(0+)$/.exec(num))) {
|
|
a.push(m[1] + "e" + m[2].length);
|
|
}
|
|
} else if ((m = /^0?\.(0+)(.*)$/.exec(num))) {
|
|
a.push(m[2] + "e-" + (m[1].length + m[2].length),
|
|
str.substr(str.indexOf(".")));
|
|
}
|
|
return best_of(a);
|
|
};
|
|
|
|
var generators = {
|
|
"string": encode_string,
|
|
"num": make_num,
|
|
"name": make_name,
|
|
"toplevel": function(statements) {
|
|
return make_block_statements(statements)
|
|
.join(newline + newline);
|
|
},
|
|
"block": make_block,
|
|
"var": function(defs) {
|
|
return "var " + add_commas(MAP(defs, make_1vardef)) + ";";
|
|
},
|
|
"const": function(defs) {
|
|
return "const " + add_commas(MAP(defs, make_1vardef)) + ";";
|
|
},
|
|
"try": function(tr, ca, fi) {
|
|
var out = [ "try", make_block(tr) ];
|
|
if (ca) out.push("catch", "(" + ca[0] + ")", make_block(ca[1]));
|
|
if (fi) out.push("finally", make_block(fi));
|
|
return add_spaces(out);
|
|
},
|
|
"throw": function(expr) {
|
|
return add_spaces([ "throw", make(expr) ]) + ";";
|
|
},
|
|
"new": function(ctor, args) {
|
|
args = args.length > 0 ? "(" + add_commas(MAP(args, make)) + ")" : "";
|
|
return add_spaces([ "new", parenthesize(ctor, "seq", "binary", "conditional", "assign", function(expr){
|
|
var w = ast_walker(), has_call = {};
|
|
try {
|
|
w.with_walkers({
|
|
"call": function() { throw has_call },
|
|
"function": function() { return this }
|
|
}, function(){
|
|
w.walk(expr);
|
|
});
|
|
} catch(ex) {
|
|
if (ex === has_call)
|
|
return true;
|
|
throw ex;
|
|
}
|
|
}) + args ]);
|
|
},
|
|
"switch": function(expr, body) {
|
|
return add_spaces([ "switch", "(" + make(expr) + ")", make_switch_block(body) ]);
|
|
},
|
|
"break": function(label) {
|
|
var out = "break";
|
|
if (label != null)
|
|
out += " " + make_name(label);
|
|
return out + ";";
|
|
},
|
|
"continue": function(label) {
|
|
var out = "continue";
|
|
if (label != null)
|
|
out += " " + make_name(label);
|
|
return out + ";";
|
|
},
|
|
"conditional": function(co, th, el) {
|
|
return add_spaces([ parenthesize(co, "assign", "seq", "conditional"), "?",
|
|
parenthesize(th, "seq"), ":",
|
|
parenthesize(el, "seq") ]);
|
|
},
|
|
"assign": function(op, lvalue, rvalue) {
|
|
if (op && op !== true) op += "=";
|
|
else op = "=";
|
|
return add_spaces([ make(lvalue), op, parenthesize(rvalue, "seq") ]);
|
|
},
|
|
"dot": function(expr) {
|
|
var out = make(expr), i = 1;
|
|
if (expr[0] == "num") {
|
|
if (!/\./.test(expr[1]))
|
|
out += ".";
|
|
} else if (needs_parens(expr))
|
|
out = "(" + out + ")";
|
|
while (i < arguments.length)
|
|
out += "." + make_name(arguments[i++]);
|
|
return out;
|
|
},
|
|
"call": function(func, args) {
|
|
var f = make(func);
|
|
if (needs_parens(func))
|
|
f = "(" + f + ")";
|
|
return f + "(" + add_commas(MAP(args, function(expr){
|
|
return parenthesize(expr, "seq");
|
|
})) + ")";
|
|
},
|
|
"function": make_function,
|
|
"defun": make_function,
|
|
"if": function(co, th, el) {
|
|
var out = [ "if", "(" + make(co) + ")", el ? make_then(th) : make(th) ];
|
|
if (el) {
|
|
out.push("else", make(el));
|
|
}
|
|
return add_spaces(out);
|
|
},
|
|
"for": function(init, cond, step, block) {
|
|
var out = [ "for" ];
|
|
init = (init != null ? make(init) : "").replace(/;*\s*$/, ";" + space);
|
|
cond = (cond != null ? make(cond) : "").replace(/;*\s*$/, ";" + space);
|
|
step = (step != null ? make(step) : "").replace(/;*\s*$/, "");
|
|
var args = init + cond + step;
|
|
if (args == "; ; ") args = ";;";
|
|
out.push("(" + args + ")", make(block));
|
|
return add_spaces(out);
|
|
},
|
|
"for-in": function(vvar, key, hash, block) {
|
|
return add_spaces([ "for", "(" +
|
|
(vvar ? make(vvar).replace(/;+$/, "") : make(key)),
|
|
"in",
|
|
make(hash) + ")", make(block) ]);
|
|
},
|
|
"while": function(condition, block) {
|
|
return add_spaces([ "while", "(" + make(condition) + ")", make(block) ]);
|
|
},
|
|
"do": function(condition, block) {
|
|
return add_spaces([ "do", make(block), "while", "(" + make(condition) + ")" ]) + ";";
|
|
},
|
|
"return": function(expr) {
|
|
var out = [ "return" ];
|
|
if (expr != null) out.push(make(expr));
|
|
return add_spaces(out) + ";";
|
|
},
|
|
"binary": function(operator, lvalue, rvalue) {
|
|
var left = make(lvalue), right = make(rvalue);
|
|
// XXX: I'm pretty sure other cases will bite here.
|
|
// we need to be smarter.
|
|
// adding parens all the time is the safest bet.
|
|
if (member(lvalue[0], [ "assign", "conditional", "seq" ]) ||
|
|
lvalue[0] == "binary" && PRECEDENCE[operator] > PRECEDENCE[lvalue[1]]) {
|
|
left = "(" + left + ")";
|
|
}
|
|
if (member(rvalue[0], [ "assign", "conditional", "seq" ]) ||
|
|
rvalue[0] == "binary" && PRECEDENCE[operator] >= PRECEDENCE[rvalue[1]] &&
|
|
!(rvalue[1] == operator && member(operator, [ "&&", "||", "*" ]))) {
|
|
right = "(" + right + ")";
|
|
}
|
|
return add_spaces([ left, operator, right ]);
|
|
},
|
|
"unary-prefix": function(operator, expr) {
|
|
var val = make(expr);
|
|
if (!(expr[0] == "num" || (expr[0] == "unary-prefix" && !HOP(OPERATORS, operator + expr[1])) || !needs_parens(expr)))
|
|
val = "(" + val + ")";
|
|
return operator + (jsp.is_alphanumeric_char(operator.charAt(0)) ? " " : "") + val;
|
|
},
|
|
"unary-postfix": function(operator, expr) {
|
|
var val = make(expr);
|
|
if (!(expr[0] == "num" || (expr[0] == "unary-postfix" && !HOP(OPERATORS, operator + expr[1])) || !needs_parens(expr)))
|
|
val = "(" + val + ")";
|
|
return val + operator;
|
|
},
|
|
"sub": function(expr, subscript) {
|
|
var hash = make(expr);
|
|
if (needs_parens(expr))
|
|
hash = "(" + hash + ")";
|
|
return hash + "[" + make(subscript) + "]";
|
|
},
|
|
"object": function(props) {
|
|
if (props.length == 0)
|
|
return "{}";
|
|
return "{" + newline + with_indent(function(){
|
|
return MAP(props, function(p){
|
|
if (p.length == 3) {
|
|
// getter/setter. The name is in p[0], the arg.list in p[1][2], the
|
|
// body in p[1][3] and type ("get" / "set") in p[2].
|
|
return indent(make_function(p[0], p[1][2], p[1][3], p[2]));
|
|
}
|
|
var key = p[0], val = make(p[1]);
|
|
if (options.quote_keys) {
|
|
key = encode_string(key);
|
|
} else if ((typeof key == "number" || !beautify && +key + "" == key)
|
|
&& parseFloat(key) >= 0) {
|
|
key = make_num(+key);
|
|
} else if (!is_identifier(key)) {
|
|
key = encode_string(key);
|
|
}
|
|
return indent(add_spaces(beautify && options.space_colon
|
|
? [ key, ":", val ]
|
|
: [ key + ":", val ]));
|
|
}).join("," + newline);
|
|
}) + newline + indent("}");
|
|
},
|
|
"regexp": function(rx, mods) {
|
|
return "/" + rx + "/" + mods;
|
|
},
|
|
"array": function(elements) {
|
|
if (elements.length == 0) return "[]";
|
|
return add_spaces([ "[", add_commas(MAP(elements, function(el){
|
|
if (!beautify && el[0] == "atom" && el[1] == "undefined") return "";
|
|
return parenthesize(el, "seq");
|
|
})), "]" ]);
|
|
},
|
|
"stat": function(stmt) {
|
|
return make(stmt).replace(/;*\s*$/, ";");
|
|
},
|
|
"seq": function() {
|
|
return add_commas(MAP(slice(arguments), make));
|
|
},
|
|
"label": function(name, block) {
|
|
return add_spaces([ make_name(name), ":", make(block) ]);
|
|
},
|
|
"with": function(expr, block) {
|
|
return add_spaces([ "with", "(" + make(expr) + ")", make(block) ]);
|
|
},
|
|
"atom": function(name) {
|
|
return make_name(name);
|
|
}
|
|
};
|
|
|
|
// The squeezer replaces "block"-s that contain only a single
|
|
// statement with the statement itself; technically, the AST
|
|
// is correct, but this can create problems when we output an
|
|
// IF having an ELSE clause where the THEN clause ends in an
|
|
// IF *without* an ELSE block (then the outer ELSE would refer
|
|
// to the inner IF). This function checks for this case and
|
|
// adds the block brackets if needed.
|
|
function make_then(th) {
|
|
if (th[0] == "do") {
|
|
// https://github.com/mishoo/UglifyJS/issues/#issue/57
|
|
// IE croaks with "syntax error" on code like this:
|
|
// if (foo) do ... while(cond); else ...
|
|
// we need block brackets around do/while
|
|
return make([ "block", [ th ]]);
|
|
}
|
|
var b = th;
|
|
while (true) {
|
|
var type = b[0];
|
|
if (type == "if") {
|
|
if (!b[3])
|
|
// no else, we must add the block
|
|
return make([ "block", [ th ]]);
|
|
b = b[3];
|
|
}
|
|
else if (type == "while" || type == "do") b = b[2];
|
|
else if (type == "for" || type == "for-in") b = b[4];
|
|
else break;
|
|
}
|
|
return make(th);
|
|
};
|
|
|
|
function make_function(name, args, body, keyword) {
|
|
var out = keyword || "function";
|
|
if (name) {
|
|
out += " " + make_name(name);
|
|
}
|
|
out += "(" + add_commas(MAP(args, make_name)) + ")";
|
|
return add_spaces([ out, make_block(body) ]);
|
|
};
|
|
|
|
function make_block_statements(statements) {
|
|
for (var a = [], last = statements.length - 1, i = 0; i <= last; ++i) {
|
|
var stat = statements[i];
|
|
var code = make(stat);
|
|
if (code != ";") {
|
|
if (!beautify && i == last) {
|
|
if ((stat[0] == "while" && empty(stat[2])) ||
|
|
(member(stat[0], [ "for", "for-in"] ) && empty(stat[4])) ||
|
|
(stat[0] == "if" && empty(stat[2]) && !stat[3]) ||
|
|
(stat[0] == "if" && stat[3] && empty(stat[3]))) {
|
|
code = code.replace(/;*\s*$/, ";");
|
|
} else {
|
|
code = code.replace(/;+\s*$/, "");
|
|
}
|
|
}
|
|
a.push(code);
|
|
}
|
|
}
|
|
return MAP(a, indent);
|
|
};
|
|
|
|
function make_switch_block(body) {
|
|
var n = body.length;
|
|
if (n == 0) return "{}";
|
|
return "{" + newline + MAP(body, function(branch, i){
|
|
var has_body = branch[1].length > 0, code = with_indent(function(){
|
|
return indent(branch[0]
|
|
? add_spaces([ "case", make(branch[0]) + ":" ])
|
|
: "default:");
|
|
}, 0.5) + (has_body ? newline + with_indent(function(){
|
|
return make_block_statements(branch[1]).join(newline);
|
|
}) : "");
|
|
if (!beautify && has_body && i < n - 1)
|
|
code += ";";
|
|
return code;
|
|
}).join(newline) + newline + indent("}");
|
|
};
|
|
|
|
function make_block(statements) {
|
|
if (!statements) return ";";
|
|
if (statements.length == 0) return "{}";
|
|
return "{" + newline + with_indent(function(){
|
|
return make_block_statements(statements).join(newline);
|
|
}) + newline + indent("}");
|
|
};
|
|
|
|
function make_1vardef(def) {
|
|
var name = def[0], val = def[1];
|
|
if (val != null)
|
|
name = add_spaces([ make_name(name), "=", parenthesize(val, "seq") ]);
|
|
return name;
|
|
};
|
|
|
|
var $stack = [];
|
|
|
|
function make(node) {
|
|
var type = node[0];
|
|
var gen = generators[type];
|
|
if (!gen)
|
|
throw new Error("Can't find generator for \"" + type + "\"");
|
|
$stack.push(node);
|
|
var ret = gen.apply(type, node.slice(1));
|
|
$stack.pop();
|
|
return ret;
|
|
};
|
|
|
|
return make(ast);
|
|
};
|
|
|
|
function split_lines(code, max_line_length) {
|
|
var splits = [ 0 ];
|
|
jsp.parse(function(){
|
|
var next_token = jsp.tokenizer(code);
|
|
var last_split = 0;
|
|
var prev_token;
|
|
function current_length(tok) {
|
|
return tok.pos - last_split;
|
|
};
|
|
function split_here(tok) {
|
|
last_split = tok.pos;
|
|
splits.push(last_split);
|
|
};
|
|
function custom(){
|
|
var tok = next_token.apply(this, arguments);
|
|
out: {
|
|
if (prev_token) {
|
|
if (prev_token.type == "keyword") break out;
|
|
}
|
|
if (current_length(tok) > max_line_length) {
|
|
switch (tok.type) {
|
|
case "keyword":
|
|
case "atom":
|
|
case "name":
|
|
case "punc":
|
|
split_here(tok);
|
|
break out;
|
|
}
|
|
}
|
|
}
|
|
prev_token = tok;
|
|
return tok;
|
|
};
|
|
custom.context = function() {
|
|
return next_token.context.apply(this, arguments);
|
|
};
|
|
return custom;
|
|
}());
|
|
return splits.map(function(pos, i){
|
|
return code.substring(pos, splits[i + 1] || code.length);
|
|
}).join("\n");
|
|
};
|
|
|
|
/* -----[ Utilities ]----- */
|
|
|
|
function repeat_string(str, i) {
|
|
if (i <= 0) return "";
|
|
if (i == 1) return str;
|
|
var d = repeat_string(str, i >> 1);
|
|
d += d;
|
|
if (i & 1) d += str;
|
|
return d;
|
|
};
|
|
|
|
function defaults(args, defs) {
|
|
var ret = {};
|
|
if (args === true)
|
|
args = {};
|
|
for (var i in defs) if (HOP(defs, i)) {
|
|
ret[i] = (args && HOP(args, i)) ? args[i] : defs[i];
|
|
}
|
|
return ret;
|
|
};
|
|
|
|
function is_identifier(name) {
|
|
return /^[a-z_$][a-z0-9_$]*$/i.test(name)
|
|
&& name != "this"
|
|
&& !HOP(jsp.KEYWORDS_ATOM, name)
|
|
&& !HOP(jsp.RESERVED_WORDS, name)
|
|
&& !HOP(jsp.KEYWORDS, name);
|
|
};
|
|
|
|
function HOP(obj, prop) {
|
|
return Object.prototype.hasOwnProperty.call(obj, prop);
|
|
};
|
|
|
|
// some utilities
|
|
|
|
var MAP;
|
|
|
|
(function(){
|
|
MAP = function(a, f, o) {
|
|
var ret = [];
|
|
for (var i = 0; i < a.length; ++i) {
|
|
var val = f.call(o, a[i], i);
|
|
if (val instanceof AtTop) ret.unshift(val.v);
|
|
else ret.push(val);
|
|
}
|
|
return ret;
|
|
};
|
|
MAP.at_top = function(val) { return new AtTop(val) };
|
|
function AtTop(val) { this.v = val };
|
|
})();
|
|
|
|
/* -----[ Exports ]----- */
|
|
|
|
exports.ast_walker = ast_walker;
|
|
exports.ast_mangle = ast_mangle;
|
|
exports.ast_squeeze = ast_squeeze;
|
|
exports.gen_code = gen_code;
|
|
exports.ast_add_scope = ast_add_scope;
|
|
exports.set_logger = function(logger) { warn = logger };
|
|
exports.make_string = make_string;
|
|
exports.split_lines = split_lines;
|
|
exports.MAP = MAP;
|
|
|
|
// keep this last!
|
|
exports.ast_squeeze_more = require("./squeeze-more").ast_squeeze_more;
|