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/* ***** BEGIN LICENSE BLOCK ****** vim: set ts=4 sw=4 et tw=80:** Version: MPL 1.1/GPL 2.0/LGPL 2.1** The contents of this file are subject to the Mozilla Public License Version* 1.1 (the "License"); you may not use this file except in compliance with* the License. You may obtain a copy of the License at* http://www.mozilla.org/MPL/** Software distributed under the License is distributed on an "AS IS" basis,* WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License* for the specific language governing rights and limitations under the* License.** The Original Code is the Narcissus JavaScript engine.** The Initial Developer of the Original Code is* Brendan Eich <brendan@mozilla.org>.* Portions created by the Initial Developer are Copyright (C) 2004* the Initial Developer. All Rights Reserved.** Contributor(s):** Alternatively, the contents of this file may be used under the terms of* either the GNU General Public License Version 2 or later (the "GPL"), or* the GNU Lesser General Public License Version 2.1 or later (the "LGPL"),* in which case the provisions of the GPL or the LGPL are applicable instead* of those above. If you wish to allow use of your version of this file only* under the terms of either the GPL or the LGPL, and not to allow others to* use your version of this file under the terms of the MPL, indicate your* decision by deleting the provisions above and replace them with the notice* and other provisions required by the GPL or the LGPL. If you do not delete* the provisions above, a recipient may use your version of this file under* the terms of any one of the MPL, the GPL or the LGPL.** ***** END LICENSE BLOCK ***** *//** Narcissus - JS implemented in JS.** Execution of parse trees.** Standard classes except for eval, Function, Array, and String are borrowed* from the host JS environment. Function is metacircular. Array and String* are reflected via wrapping the corresponding native constructor and adding* an extra level of prototype-based delegation.*/// jrh//module('JS.Exec');// end jrhGLOBAL_CODE = 0; EVAL_CODE = 1; FUNCTION_CODE = 2;function ExecutionContext(type) {this.type = type;}// jrhvar agenda = new Array();var skip_setup = 0;// end jrhvar global = {// Value properties.NaN: NaN, Infinity: Infinity, undefined: undefined,alert : function(msg) { alert(msg) },confirm : function(msg) { return confirm(msg) },document : document,window : window,// jrh//debug: window.open('','debugwindow','width=600,height=400,scrollbars=yes,resizable=yes'),// end jrhnavigator : navigator,XMLHttpRequest : function() { return new XMLHttpRequest() },// Function properties.eval: function(s) {if (typeof s != "string") {return s;}var x = ExecutionContext.current;var x2 = new ExecutionContext(EVAL_CODE);x2.thisObject = x.thisObject;x2.caller = x.caller;x2.callee = x.callee;x2.scope = x.scope;ExecutionContext.current = x2;try {execute(parse(s), x2);} catch (e) {x.result = x2.result;throw e;} finally {ExecutionContext.current = x;}return x2.result;},parseInt: parseInt, parseFloat: parseFloat,isNaN: isNaN, isFinite: isFinite,decodeURI: decodeURI, encodeURI: encodeURI,decodeURIComponent: decodeURIComponent,encodeURIComponent: encodeURIComponent,// Class constructors. Where ECMA-262 requires C.length == 1, we declare// a dummy formal parameter.Object: Object,Function: function(dummy) {var p = "", b = "", n = arguments.length;if (n) {var m = n - 1;if (m) {p += arguments[0];for (var k = 1; k < m; k++)p += "," + arguments[k];}b += arguments[m];}// XXX We want to pass a good file and line to the tokenizer.// Note the anonymous name to maintain parity with Spidermonkey.var t = new Tokenizer("anonymous(" + p + ") {" + b + "}");// NB: Use the STATEMENT_FORM constant since we don't want to push this// function onto the null compilation context.var f = FunctionDefinition(t, null, false, STATEMENT_FORM);var s = {object: global, parent: null};return new FunctionObject(f, s);},Array: function(dummy) {// Array when called as a function acts as a constructor.return GLOBAL.Array.apply(this, arguments);},String: function(s) {// Called as function or constructor: convert argument to string type.s = arguments.length ? "" + s : "";if (this instanceof String) {// Called as constructor: save the argument as the string value// of this String object and return this object.this.value = s;return this;}return s;},Boolean: Boolean, Number: Number, Date: Date, RegExp: RegExp,Error: Error, EvalError: EvalError, RangeError: RangeError,ReferenceError: ReferenceError, SyntaxError: SyntaxError,TypeError: TypeError, URIError: URIError,// Other properties.Math: Math,// Extensions to ECMA.//snarf: snarf,evaluate: evaluate,load: function(s) {if (typeof s != "string")return s;var req = new XMLHttpRequest();req.open('GET', s, false);req.send(null);evaluate(req.responseText, s, 1)},print: print, version: null};// jrh//global.debug.document.body.innerHTML = ''// end jrh// Helper to avoid Object.prototype.hasOwnProperty polluting scope objects.function hasDirectProperty(o, p) {return Object.prototype.hasOwnProperty.call(o, p);}// Reflect a host class into the target global environment by delegation.function reflectClass(name, proto) {var gctor = global[name];gctor.prototype = proto;proto.constructor = gctor;return proto;}// Reflect Array -- note that all Array methods are generic.reflectClass('Array', new Array);// Reflect String, overriding non-generic methods.var gSp = reflectClass('String', new String);gSp.toSource = function () { return this.value.toSource(); };gSp.toString = function () { return this.value; };gSp.valueOf = function () { return this.value; };global.String.fromCharCode = String.fromCharCode;var XCp = ExecutionContext.prototype;ExecutionContext.current = XCp.caller = XCp.callee = null;XCp.scope = {object: global, parent: null};XCp.thisObject = global;XCp.result = undefined;XCp.target = null;XCp.ecmaStrictMode = false;function Reference(base, propertyName, node) {this.base = base;this.propertyName = propertyName;this.node = node;}Reference.prototype.toString = function () { return this.node.getSource(); }function getValue(v) {if (v instanceof Reference) {if (!v.base) {throw new ReferenceError(v.propertyName + " is not defined",v.node.filename(), v.node.lineno);}return v.base[v.propertyName];}return v;}function putValue(v, w, vn) {if (v instanceof Reference)return (v.base || global)[v.propertyName] = w;throw new ReferenceError("Invalid assignment left-hand side",vn.filename(), vn.lineno);}function isPrimitive(v) {var t = typeof v;return (t == "object") ? v === null : t != "function";}function isObject(v) {var t = typeof v;return (t == "object") ? v !== null : t == "function";}// If r instanceof Reference, v == getValue(r); else v === r. If passed, rn// is the node whose execute result was r.function toObject(v, r, rn) {switch (typeof v) {case "boolean":return new global.Boolean(v);case "number":return new global.Number(v);case "string":return new global.String(v);case "function":return v;case "object":if (v !== null)return v;}var message = r + " (type " + (typeof v) + ") has no properties";throw rn ? new TypeError(message, rn.filename(), rn.lineno): new TypeError(message);}function execute(n, x) {if (!this.new_block)new_block = new Array();//alert (n)var a, f, i, j, r, s, t, u, v;switch (n.type) {case FUNCTION:if (n.functionForm != DECLARED_FORM) {if (!n.name || n.functionForm == STATEMENT_FORM) {v = new FunctionObject(n, x.scope);if (n.functionForm == STATEMENT_FORM)x.scope.object[n.name] = v;} else {t = new Object;x.scope = {object: t, parent: x.scope};try {v = new FunctionObject(n, x.scope);t[n.name] = v;} finally {x.scope = x.scope.parent;}}}break;case SCRIPT:t = x.scope.object;a = n.funDecls;for (i = 0, j = a.length; i < j; i++) {s = a[i].name;f = new FunctionObject(a[i], x.scope);t[s] = f;}a = n.varDecls;for (i = 0, j = a.length; i < j; i++) {u = a[i];s = u.name;if (u.readOnly && hasDirectProperty(t, s)) {throw new TypeError("Redeclaration of const " + s,u.filename(), u.lineno);}if (u.readOnly || !hasDirectProperty(t, s)) {t[s] = null;}}// FALL THROUGHcase BLOCK:for (i = 0, j = n.$length; i < j; i++) {//jrh//execute(n[i], x);//new_block.unshift([n[i], x]);new_block.push([n[i], x]);}new_block.reverse();agenda = agenda.concat(new_block);//agenda = new_block.concat(agenda)// end jrhbreak;case IF:if (getValue(execute(n.condition, x)))execute(n.thenPart, x);else if (n.elsePart)execute(n.elsePart, x);break;case SWITCH:s = getValue(execute(n.discriminant, x));a = n.cases;var matchDefault = false;switch_loop:for (i = 0, j = a.length; ; i++) {if (i == j) {if (n.defaultIndex >= 0) {i = n.defaultIndex - 1; // no case matched, do defaultmatchDefault = true;continue;}break; // no default, exit switch_loop}t = a[i]; // next case (might be default!)if (t.type == CASE) {u = getValue(execute(t.caseLabel, x));} else {if (!matchDefault) // not defaulting, skip for nowcontinue;u = s; // force match to do default}if (u === s) {for (;;) { // this loop exits switch_loopif (t.statements.length) {try {execute(t.statements, x);} catch (e) {if (!(e == BREAK && x.target == n)) { throw e }break switch_loop;}}if (++i == j)break switch_loop;t = a[i];}// NOT REACHED}}break;case FOR:// jrh// added "skip_setup" so initialization doesn't get called// on every call..if (!skip_setup)n.setup && getValue(execute(n.setup, x));// FALL THROUGHcase WHILE:// jrh//while (!n.condition || getValue(execute(n.condition, x))) {if (!n.condition || getValue(execute(n.condition, x))) {try {// jrh//execute(n.body, x);new_block.push([n.body, x]);agenda.push([n.body, x])//agenda.unshift([n.body, x])// end jrh} catch (e) {if (e == BREAK && x.target == n) {break;} else if (e == CONTINUE && x.target == n) {// jrh// 'continue' is invalid inside an 'if' clause// I don't know what commenting this out will break!//continue;// end jrh} else {throw e;}}n.update && getValue(execute(n.update, x));// jrhnew_block.unshift([n, x])agenda.splice(agenda.length-1,0,[n, x])//agenda.splice(1,0,[n, x])skip_setup = 1// end jrh} else {skip_setup = 0}break;case FOR_IN:u = n.varDecl;if (u)execute(u, x);r = n.iterator;s = execute(n.object, x);v = getValue(s);// ECMA deviation to track extant browser JS implementation behavior.t = (v == null && !x.ecmaStrictMode) ? v : toObject(v, s, n.object);a = [];for (i in t)a.push(i);for (i = 0, j = a.length; i < j; i++) {putValue(execute(r, x), a[i], r);try {execute(n.body, x);} catch (e) {if (e == BREAK && x.target == n) {break;} else if (e == CONTINUE && x.target == n) {continue;} else {throw e;}}}break;case DO:do {try {execute(n.body, x);} catch (e) {if (e == BREAK && x.target == n) {break;} else if (e == CONTINUE && x.target == n) {continue;} else {throw e;}}} while (getValue(execute(n.condition, x)));break;case BREAK:case CONTINUE:x.target = n.target;throw n.type;case TRY:try {execute(n.tryBlock, x);} catch (e) {if (!(e == THROW && (j = n.catchClauses.length))) {throw e;}e = x.result;x.result = undefined;for (i = 0; ; i++) {if (i == j) {x.result = e;throw THROW;}t = n.catchClauses[i];x.scope = {object: {}, parent: x.scope};x.scope.object[t.varName] = e;try {if (t.guard && !getValue(execute(t.guard, x)))continue;execute(t.block, x);break;} finally {x.scope = x.scope.parent;}}} finally {if (n.finallyBlock)execute(n.finallyBlock, x);}break;case THROW:x.result = getValue(execute(n.exception, x));throw THROW;case RETURN:x.result = getValue(execute(n.value, x));throw RETURN;case WITH:r = execute(n.object, x);t = toObject(getValue(r), r, n.object);x.scope = {object: t, parent: x.scope};try {execute(n.body, x);} finally {x.scope = x.scope.parent;}break;case VAR:case CONST:for (i = 0, j = n.$length; i < j; i++) {u = n[i].initializer;if (!u)continue;t = n[i].name;for (s = x.scope; s; s = s.parent) {if (hasDirectProperty(s.object, t))break;}u = getValue(execute(u, x));if (n.type == CONST)s.object[t] = u;elses.object[t] = u;}break;case DEBUGGER:throw "NYI: " + tokens[n.type];case REQUIRE:var req = new XMLHttpRequest();req.open('GET', n.filename, 'false');case SEMICOLON:if (n.expression)// print debugging statementsvar the_start = n.startvar the_end = n.endvar the_statement = parse_result.tokenizer.source.slice(the_start,the_end)//global.debug.document.body.innerHTML += ('<pre>>>> <b>' + the_statement + '</b></pre>')LOG.info('>>>' + the_statement)x.result = getValue(execute(n.expression, x));//if (x.result)//global.debug.document.body.innerHTML += ( '<pre>>>> ' + x.result + '</pre>')break;case LABEL:try {execute(n.statement, x);} catch (e) {if (!(e == BREAK && x.target == n)) { throw e }}break;case COMMA:for (i = 0, j = n.$length; i < j; i++)v = getValue(execute(n[i], x));break;case ASSIGN:r = execute(n[0], x);t = n[0].assignOp;if (t)u = getValue(r);v = getValue(execute(n[1], x));if (t) {switch (t) {case BITWISE_OR: v = u | v; break;case BITWISE_XOR: v = u ^ v; break;case BITWISE_AND: v = u & v; break;case LSH: v = u << v; break;case RSH: v = u >> v; break;case URSH: v = u >>> v; break;case PLUS: v = u + v; break;case MINUS: v = u - v; break;case MUL: v = u * v; break;case DIV: v = u / v; break;case MOD: v = u % v; break;}}putValue(r, v, n[0]);break;case CONDITIONAL:v = getValue(execute(n[0], x)) ? getValue(execute(n[1], x)): getValue(execute(n[2], x));break;case OR:v = getValue(execute(n[0], x)) || getValue(execute(n[1], x));break;case AND:v = getValue(execute(n[0], x)) && getValue(execute(n[1], x));break;case BITWISE_OR:v = getValue(execute(n[0], x)) | getValue(execute(n[1], x));break;case BITWISE_XOR:v = getValue(execute(n[0], x)) ^ getValue(execute(n[1], x));break;case BITWISE_AND:v = getValue(execute(n[0], x)) & getValue(execute(n[1], x));break;case EQ:v = getValue(execute(n[0], x)) == getValue(execute(n[1], x));break;case NE:v = getValue(execute(n[0], x)) != getValue(execute(n[1], x));break;case STRICT_EQ:v = getValue(execute(n[0], x)) === getValue(execute(n[1], x));break;case STRICT_NE:v = getValue(execute(n[0], x)) !== getValue(execute(n[1], x));break;case LT:v = getValue(execute(n[0], x)) < getValue(execute(n[1], x));break;case LE:v = getValue(execute(n[0], x)) <= getValue(execute(n[1], x));break;case GE:v = getValue(execute(n[0], x)) >= getValue(execute(n[1], x));break;case GT:v = getValue(execute(n[0], x)) > getValue(execute(n[1], x));break;case IN:v = getValue(execute(n[0], x)) in getValue(execute(n[1], x));break;case INSTANCEOF:t = getValue(execute(n[0], x));u = getValue(execute(n[1], x));if (isObject(u) && typeof u.__hasInstance__ == "function")v = u.__hasInstance__(t);elsev = t instanceof u;break;case LSH:v = getValue(execute(n[0], x)) << getValue(execute(n[1], x));break;case RSH:v = getValue(execute(n[0], x)) >> getValue(execute(n[1], x));break;case URSH:v = getValue(execute(n[0], x)) >>> getValue(execute(n[1], x));break;case PLUS:v = getValue(execute(n[0], x)) + getValue(execute(n[1], x));break;case MINUS:v = getValue(execute(n[0], x)) - getValue(execute(n[1], x));break;case MUL:v = getValue(execute(n[0], x)) * getValue(execute(n[1], x));break;case DIV:v = getValue(execute(n[0], x)) / getValue(execute(n[1], x));break;case MOD:v = getValue(execute(n[0], x)) % getValue(execute(n[1], x));break;case DELETE:t = execute(n[0], x);v = !(t instanceof Reference) || delete t.base[t.propertyName];break;case VOID:getValue(execute(n[0], x));break;case TYPEOF:t = execute(n[0], x);if (t instanceof Reference)t = t.base ? t.base[t.propertyName] : undefined;v = typeof t;break;case NOT:v = !getValue(execute(n[0], x));break;case BITWISE_NOT:v = ~getValue(execute(n[0], x));break;case UNARY_PLUS:v = +getValue(execute(n[0], x));break;case UNARY_MINUS:v = -getValue(execute(n[0], x));break;case INCREMENT:case DECREMENT:t = execute(n[0], x);u = Number(getValue(t));if (n.postfix)v = u;putValue(t, (n.type == INCREMENT) ? ++u : --u, n[0]);if (!n.postfix)v = u;break;case DOT:r = execute(n[0], x);t = getValue(r);u = n[1].value;v = new Reference(toObject(t, r, n[0]), u, n);break;case INDEX:r = execute(n[0], x);t = getValue(r);u = getValue(execute(n[1], x));v = new Reference(toObject(t, r, n[0]), String(u), n);break;case LIST:// Curse ECMA for specifying that arguments is not an Array object!v = {};for (i = 0, j = n.$length; i < j; i++) {u = getValue(execute(n[i], x));v[i] = u;}v.length = i;break;case CALL:r = execute(n[0], x);a = execute(n[1], x);f = getValue(r);if (isPrimitive(f) || typeof f.__call__ != "function") {throw new TypeError(r + " is not callable",n[0].filename(), n[0].lineno);}t = (r instanceof Reference) ? r.base : null;if (t instanceof Activation)t = null;v = f.__call__(t, a, x);break;case NEW:case NEW_WITH_ARGS:r = execute(n[0], x);f = getValue(r);if (n.type == NEW) {a = {};a.length = 0;} else {a = execute(n[1], x);}if (isPrimitive(f) || typeof f.__construct__ != "function") {throw new TypeError(r + " is not a constructor",n[0].filename(), n[0].lineno);}v = f.__construct__(a, x);break;case ARRAY_INIT:v = [];for (i = 0, j = n.$length; i < j; i++) {if (n[i])v[i] = getValue(execute(n[i], x));}v.length = j;break;case OBJECT_INIT:v = {};for (i = 0, j = n.$length; i < j; i++) {t = n[i];if (t.type == PROPERTY_INIT) {v[t[0].value] = getValue(execute(t[1], x));} else {f = new FunctionObject(t, x.scope);/*u = (t.type == GETTER) ? '__defineGetter__': '__defineSetter__';v[u](t.name, thunk(f, x));*/}}break;case NULL:v = null;break;case THIS:v = x.thisObject;break;case TRUE:v = true;break;case FALSE:v = false;break;case IDENTIFIER:for (s = x.scope; s; s = s.parent) {if (n.value in s.object)break;}v = new Reference(s && s.object, n.value, n);break;case NUMBER:case STRING:case REGEXP:v = n.value;break;case GROUP:v = execute(n[0], x);break;default:throw "PANIC: unknown operation " + n.type + ": " + uneval(n);}return v;}function Activation(f, a) {for (var i = 0, j = f.params.length; i < j; i++)this[f.params[i]] = a[i];this.arguments = a;}// Null Activation.prototype's proto slot so that Object.prototype.* does not// pollute the scope of heavyweight functions. Also delete its 'constructor'// property so that it doesn't pollute function scopes.Activation.prototype.__proto__ = null;delete Activation.prototype.constructor;function FunctionObject(node, scope) {this.node = node;this.scope = scope;this.length = node.params.length;var proto = {};this.prototype = proto;proto.constructor = this;}var FOp = FunctionObject.prototype = {// Internal methods.__call__: function (t, a, x) {var x2 = new ExecutionContext(FUNCTION_CODE);x2.thisObject = t || global;x2.caller = x;x2.callee = this;a.callee = this;var f = this.node;x2.scope = {object: new Activation(f, a), parent: this.scope};ExecutionContext.current = x2;try {execute(f.body, x2);} catch (e) {if (!(e == RETURN)) { throw e } else if (e == RETURN) {return x2.result;}if (e != THROW) { throw e }x.result = x2.result;throw THROW;} finally {ExecutionContext.current = x;}return undefined;},__construct__: function (a, x) {var o = new Object;var p = this.prototype;if (isObject(p))o.__proto__ = p;// else o.__proto__ defaulted to Object.prototypevar v = this.__call__(o, a, x);if (isObject(v))return v;return o;},__hasInstance__: function (v) {if (isPrimitive(v))return false;var p = this.prototype;if (isPrimitive(p)) {throw new TypeError("'prototype' property is not an object",this.node.filename(), this.node.lineno);}var o;while ((o = v.__proto__)) {if (o == p)return true;v = o;}return false;},// Standard methods.toString: function () {return this.node.getSource();},apply: function (t, a) {// Curse ECMA again!if (typeof this.__call__ != "function") {throw new TypeError("Function.prototype.apply called on" +" uncallable object");}if (t === undefined || t === null)t = global;else if (typeof t != "object")t = toObject(t, t);if (a === undefined || a === null) {a = {};a.length = 0;} else if (a instanceof Array) {var v = {};for (var i = 0, j = a.length; i < j; i++)v[i] = a[i];v.length = i;a = v;} else if (!(a instanceof Object)) {// XXX check for a non-arguments objectthrow new TypeError("Second argument to Function.prototype.apply" +" must be an array or arguments object",this.node.filename(), this.node.lineno);}return this.__call__(t, a, ExecutionContext.current);},call: function (t) {// Curse ECMA a third time!var a = Array.prototype.splice.call(arguments, 1);return this.apply(t, a);}};// Connect Function.prototype and Function.prototype.constructor in global.reflectClass('Function', FOp);// Help native and host-scripted functions be like FunctionObjects.var Fp = Function.prototype;var REp = RegExp.prototype;if (!('__call__' in Fp)) {Fp.__call__ = function (t, a, x) {// Curse ECMA yet again!a = Array.prototype.splice.call(a, 0, a.length);return this.apply(t, a);};REp.__call__ = function (t, a, x) {a = Array.prototype.splice.call(a, 0, a.length);return this.exec.apply(this, a);};Fp.__construct__ = function (a, x) {switch (a.length) {case 0:return new this();case 1:return new this(a[0]);case 2:return new this(a[0], a[1]);case 3:return new this(a[0], a[1], a[2]);case 4:return new this(a[0], a[1], a[2], a[3]);case 5:return new this(a[0], a[1], a[2], a[3], a[4]);case 6:return new this(a[0], a[1], a[2], a[3], a[4], a[5]);case 7:return new this(a[0], a[1], a[2], a[3], a[4], a[5], a[6]);}throw "PANIC: too many arguments to constructor";}// Since we use native functions such as Date along with host ones such// as global.eval, we want both to be considered instances of the native// Function constructor.Fp.__hasInstance__ = function (v) {return v instanceof Function || v instanceof global.Function;};}function thunk(f, x) {return function () { return f.__call__(this, arguments, x); };}function evaluate(s, f, l) {if (typeof s != "string")return s;var x = ExecutionContext.current;var x2 = new ExecutionContext(GLOBAL_CODE);ExecutionContext.current = x2;try {execute(parse(s, f, l), x2);} catch (e) {if (e != THROW) { throw e }if (x) {x.result = x2.result;throw(THROW);}throw x2.result;} finally {ExecutionContext.current = x;}return x2.result;}