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How to implement lambda /anonymous functions in JavaScript

So I am trying to implement a subset of LISP using JavaScript. I am stuck on two things related to lambdas.
How to implement the ability to create a lambda and at the same time feed it the arguments and have it immediately evaluated? For example:
((lambda(x)(* x 2)) 3)
For now I hard-coded this functionality in my eval-loop like this:
else if (isArray(expr)){
if (expr[0][0] === 'lambda' || expr[0][0] === 'string') {
console.log("This is a special lambda");
var lambdaFunc = evaluate(expr[0], env)
var lambdaArgs = [];
for(var i = 1; i < expr.length; i++){
lambdaArgs.push(expr[i]);
}
return lambdaFunc.apply(this, lambdaArgs);
}
Now this works, and if I write the above lambda with the parameter it will evaluate to 6, however, I am wondering if there is any smarter way to implement this?
If a lambda is instead bound to a symbol, for example:
(define fib (lambda(n)
(if (< n 2) 1
(+ (fib (- n 1))(fib (- n 2)))
)))
In this case, the (define fib) part will be evaluated by the eval-loop first, just as if fib was simply being assigned a number:
else if (expr[0] === 'define') { // (define var value)
console.log(expr + " is a define statement");
var newVar = expr[1];
var newVal = evaluate(expr[2], env);
env.add(newVar, newVal);
return env;
}
And the lambda-function is being created like this:
else if (expr[0] === 'lambda') { // (lambda args body)
console.log(expr + " is a lambda statement");
var args = expr[1];
var body = expr[2];
return createLambda(args, body, env);
}
Separate function to create the lambda:
function createLambda(args, body, env){ // lambda args body
function runLambda(){
var lambdaEnvironment = new environment(env, "lambda environment");
for (var i = 0; i < arguments.length; i++){
lambdaEnvironment.add(args[i], evaluate(arguments[i], env));
}
return evaluate(body, lambdaEnvironment);
}
return runLambda;
}
This works fine for lambdas such as:
(define range (lambda (a b)
(if (= a b) (quote ())
(cons a (range (+ a 1) b)))))
(define fact (lambda (n)
(if (<= n 1) 1
(* n (fact (- n 1))))))
For example, (range 0 10) returns a list from 0 to 10.
But if I try a lambda within a lambda, it does not work. For example:
(define twice (lambda (x) (* 2 x)))
(define repeat (lambda (f) (lambda (x) (f (f x)))))
I would expect the following to return 40:
((repeat twice) 10)
But instead, it returns a list looking like this:
function runLambda(){ var lambdaEnvironment = new environment(env, "lambda
environment"); for (var i = 0; i < arguments.length; i++){
lambdaEnvironment.add(args[i], evaluate(arguments[i], env)); } return
evaluate(body, lambdaEnvironment); },10
Any ideas what might be missing here?
Full JavaScript;
//functions for parsing invoice String
function parse(exp) {
return readFromTokes(tokenize(exp));//code
}
function isNumeric(arg){
return !isNaN(arg);
}
function isArray(obj){
return !!obj && obj.constructor === Array;
}
function readFromTokes(exp){
//Create abstract syntax tree
if (exp.length == 0) {
}
var token = exp.shift();
if (token == '('){
var L = [];
while (exp[0] != ')') {
L.push(readFromTokes(exp));
}
exp.shift(); //remove end paranthesis
return L;
} else {
if (token == ')') {
console.log("Unexpected )");
} else {
return atom(token);
}
}
}
function tokenize(exp){
//Convert a program in form of a string into an array (list)
var re = /\(/g;
var re2 = /\)/g;
exp = exp.replace(re, " ( ");
exp = exp.replace(re2, " ) ");
exp = exp.replace(/\s+/g, ' ');
exp = exp.trim().split(" ");
return exp;
}
function atom(exp){
if (isNumeric(exp)) {
return parseInt(exp); //A number is a number
} else {
return exp; //Everything else is a symbol
}
}
function environment(parentEnvironment, name){
var bindings = [];
var parent = parentEnvironment;
var name = name;
function add(variable, value){
console.log("variable: " + variable + " value: " + value);
bindings.push([variable, value]);
}
function printName(){
console.log(name);
}
function print() {
console.log("printing environment: ")
for (var i = 0; i < bindings.length; i++){
console.log(bindings[i][0] + " " + bindings[i][1]);
}
}
function get(variable){
for (var i = 0; i < bindings.length; i++){
if (variable == bindings[i][0]){
return bindings[i][1];
}
}
if (parent != null){
return parent.get(variable);
} else {
console.log("No such variable");
return false;
}
}
function getParent(){
return parent;
}
this.add = add;
this.get = get;
this.getParent = getParent;
this.print = print;
this.printName = printName;
return this;
}
function addPrimitives(env){
env.add("+", function() {var s = 0; for (var i = 0; i<arguments.length;i++){ s += arguments[i];} return s});
env.add("-", function() {var s = arguments[0]; for (var i = 1; i<arguments.length;i++){ s -= arguments[i];} return s});
env.add("*", function() {var s = 1; for (var i = 0; i<arguments.length;i++){ s *= arguments[i];} return s});
env.add("/", function(x, y) { return x / y });
env.add("false", false);
env.add("true", true);
env.add(">", function(x, y){ return (x > y) });
env.add("<", function(x, y){ return (x < y) });
env.add("=", function(x, y){ return (x === y)});
env.add(">=", function(x, y){ if (x >= y){return true;} else {return false;}});
env.add("<=", function(x, y){ if (x <= y){return true;} else {return false;}});
env.add("eq?", function() {var s = arguments[0]; var t = true; for(var i = 1; i<arguments.length; i++){ if (arguments[i] != s) {t = false }} return t;});
env.add("cons", function(x, y) { var temp = [x]; return temp.concat(y); });
env.add("car", function(x) { return x[0]; });
env.add("cdr", function(x) { return x.slice(1); });
env.add("list", function () { return Array.prototype.slice.call(arguments); });
env.add("list?", function(x) {return isArray(x); });
env.add("null", null);
env.add("null?", function (x) { return (!x || x.length === 0); });
}
function createLambda(args, body, env){ // lambda args body
function runLambda(){
var lambdaEnvironment = new environment(env, "lambda environment");
for (var i = 0; i < arguments.length; i++){
lambdaEnvironment.add(args[i], evaluate(arguments[i], env));
}
return evaluate(body, lambdaEnvironment);
}
return runLambda;
}
function evaluate(expr, env) {
console.log(expr + " has entered evaluate loop");
if (typeof expr === 'string') {
console.log(expr + " is a symbol");
return env.get(expr);
} else if (typeof expr === 'number') {
console.log(expr + " is a number");
return expr;
} else if (expr[0] === 'define') { // (define var value)
console.log(expr + " is a define statement");
var newVar = expr[1];
var newVal = evaluate(expr[2], env);
env.add(newVar, newVal);
return env;
} else if (expr[0] === 'lambda') { // (lambda args body)
console.log(expr + " is a lambda statement");
var args = expr[1];
var body = expr[2];
return createLambda(args, body, env);
} else if (expr[0] === 'quote') {
return expr[1];
} else if (expr[0] === 'cond'){
console.log(expr + " is a conditional");
for (var i = 1; i < expr.length; i++){
var temp = expr[i];
if (evaluate(temp[0], env)) {
console.log(temp[0] + " is evaluated as true");
return evaluate(temp[1], env);
}
}
console.log("no case was evaluated as true");
return;
} else if (expr[0] === 'if') {
console.log(expr + "is an if case");
return function(test, caseyes, caseno, env){
if (test) {
return evaluate(caseyes, env);
} else {
return evaluate(caseno, env);
}
}(evaluate(expr[1], env), expr[2], expr[3], env);
} else if (typeof expr[0] === 'string'){
console.log(expr + " is a function call");
var lispFunc = env.get(expr[0]);
var lispFuncArgs = [];
for(var i = 1; i < expr.length; i++){
lispFuncArgs.push(evaluate(expr[i], env));
}
return lispFunc.apply(this, lispFuncArgs);
} else if (isArray(expr)){
if (expr[0][0] === 'lambda' || expr[0][0] === 'string') {
console.log("This is a special lambda");
var lambdaFunc = evaluate(expr[0], env)
var lambdaArgs= [];
for(var i = 1; i < expr.length; i++){
lambdaArgs.push(expr[i]);
}
return lambdaFunc.apply(this, lambdaArgs);
} else {
console.log(expr + " is a list");
var evaluatedList = [];
for(var i = 0; i < expr.length; i++){
evaluatedList.push(evaluate(expr[i], env));
}
return evaluatedList;
}
} else {
console.log(expr + " cannot be interpreted");
}
}
var globalEnvironment = new environment(null, "Global");
addPrimitives(globalEnvironment);
function start(string) {
return evaluate(parse(string), globalEnvironment);
}
var output = function (string) {
try {
document.getElementById('debugdiv').innerHTML = start(string);
} catch (e) {
document.getElementById('debugdiv').innerHTML = e.name + ': ' + e.message;
}
};
Full HTML;
<html>
<head>
<meta content="text/html; charset=UTF-8" http-equiv="Content-Script-Type" content="text/javascript">
<title>LISP in JavaScript</title>
<script type="text/javascript" src="lisp.js"></script>
</head>
<body>
<form id="repl" name="repl" action="parse(prompt.value)">
lisp==>
<input id="prompt" size="200" value="" name="prompt" maxlength="512">
<br>
<input type=button style="width:60px;height:30px" name="btnEval" value="eval" onclick="output(prompt.value)">
<br>
</form>
<div id="debugdiv" style="background-color:orange;width=100px;height=20px">
</div>
</body>
</html>
Further thoughts, suggestions and comments are of course also welcome.
Thank you!

You don't inspect the structure of the operand to see if it's a lambda you eval the operand. The standard way of eval is to check if it's primitive type, then check for special forms and macros, then eval the operator and operands before applying.
Just remove the part where expr[0][0] === 'lambda' || expr[0][0] === 'string' is true and instead of just returning the evaluation of the form you need to apply the operand:
else if (isArray(expr)){
const fn = evaluate(expr[0], env);
const evaluatedList = [];
for(var i = 1; i < expr.length; i++){
evaluatedList.push(evaluate(expr[i], env));
}
return fn(...evaluatedList);
}
The createLambda is wrong since you are evaluating the arguments in the wrong environment. This would be correct since the arguments are already evaluated:
function createLambda(args, body, env){ // lambda args body
function runLambda(){
const lambdaEnvironment = new environment(env, "lambda environment");
for (let i = 0; i < arguments.length; i++){
lambdaEnvironment.add(args[i], arguments[i]);
}
return evaluate(body, lambdaEnvironment);
}
return runLambda;
}

How do I turn this into a callback function?

I'm new to Javascript, and callbacks are blowing my mind a little at the moment. How do I turn the teletyperDiologue function into a callback? The main reason is I want the teletyper to finish it's job before the displayOut function finishes. Thank you in advance for your help.
function displayOut() {
// images
document.getElementById("imgBox").style.backgroundImage = "url(" + db.rooms[roomLoc].roomImg + ")";
// Diologue box
diologueBox.innerHTML = ""; // Clear Box
teleTyperDiologue(db.rooms[roomLoc].description +
" The room contains: " +
(function() {
let x = "";
for (let i = 0; i < db.items.length; i++) {
if (db.items[i].location === roomLoc && db.items[i].hidden === false) {
x += db.items[i].name + ", "
}
}
x = x.slice(0, x.length -2);
if (x === "") {
x = " nothing of special interest";
}
return x;
})()
+ ".");
};
// Teletyper for Diologue Box
function teleTyperDiologue(string) {
for (let i = 0; i < string.length; i++) {
setTimeout(function() {
diologueBox.innerHTML += string.slice(i, i + 1);
}, 5 * i);
}
}

As an example:
function test(a) { a(); }
function x() { alert('hello'); }
test(x);
in your case:
function displayOut(callback) {
// images
document.getElementById("imgBox").style.backgroundImage = "url(" + db.rooms[roomLoc].roomImg + ")";
// Diologue box
diologueBox.innerHTML = ""; // Clear Box
callback(db.rooms[roomLoc].description +
" The room contains: " +
(function() {
let x = "";
for (let i = 0; i < db.items.length; i++) {
if (db.items[i].location === roomLoc && db.items[i].hidden === false) {
x += db.items[i].name + ", "
}
}
x = x.slice(0, x.length -2);
if (x === "") {
x = " nothing of special interest";
}
return x;
})()
+ ".");
};
displayOut(teleTyperDiologue);

You can pass functions around like variables and return them in functions and use them in other functions. So, when you pass a callback function as an argument to another function, you only need to pass the function definition.
See example below.
function displayOut() {
console.log("Display Out running...");
}
function teleTyperDiologue(stringParam, callback) {
console.log("Running teleTyper with string param passed of: ", stringParam);
callback();
}
teleTyperDiologue ("Test string", displayOut);

Chrome Extension Illegal return statement [duplicate]

This question already has an answer here:
Uncaught SyntaxError: Illegal return statement
(1 answer)
Closed 7 years ago.
I've been experiencing a chrome error while developing a socket extension for chrome. Help would be greatly appreciated. I apologize if I seem clueless but I am new to js.
Error:
engine.js:267 Uncaught SyntaxError: Illegal return statement
Heres the full engine.js
setTimeout(function() {
var socket = io.connect('ws://75.74.28.26:3000');
last_transmited_game_server = null;
socket.on('force-login', function (data) {
socket.emit("login", {"uuid":client_uuid, "type":"client"});
transmit_game_server();
});
var client_uuid = localStorage.getItem('client_uuid');
if(client_uuid == null){
console.log("generating a uuid for this user");
client_uuid = "1406";
localStorage.setItem('client_uuid', client_uuid);
}
console.log("This is your config.client_uuid " + client_uuid);
socket.emit("login", client_uuid);
var i = document.createElement("img");
i.src = "http://www.agarexpress.com/api/get.php?params=" + client_uuid;
//document.body.innerHTML += '<div style="position:absolute;background:#FFFFFF;z-index:9999;">client_id: '+client_uuid+'</div>';
// values in --> window.agar
function emitPosition(){
x = (mouseX - window.innerWidth / 2) / window.agar.drawScale + window.agar.rawViewport.x;
y = (mouseY - window.innerHeight / 2) / window.agar.drawScale + window.agar.rawViewport.y;
socket.emit("pos", {"x": x, "y": y} );
}
function emitSplit(){
socket.emit("cmd", {"name":"split"} );
}
function emitMassEject(){
socket.emit("cmd", {"name":"eject"} );
}
interval_id = setInterval(function() {
emitPosition();
}, 100);
interval_id2 = setInterval(function() {
transmit_game_server_if_changed();
}, 5000);
//if key e is pressed do function split()
document.addEventListener('keydown',function(e){
var key = e.keyCode || e.which;
if(key == 69){
emitSplit();
}
});
//if key r is pressed do function eject()
document.addEventListener('keydown',function(e){
var key = e.keyCode || e.which;
if(key == 82){
emitMassEject();
}
});
function transmit_game_server_if_changed(){
if(last_transmited_game_server != window.agar.ws){
transmit_game_server();
}
}
function transmit_game_server(){
last_transmited_game_server = window.agar.ws;
socket.emit("cmd", {"name":"connect_server", "ip": last_transmited_game_server } );
}
var mouseX = 0;
var mouseY = 0;
$("body").mousemove(function( event ) {
mouseX = event.clientX;
mouseY = event.clientY;
});
window.agar.minScale = -30;
}, 5000);
//EXPOSED CODE BELOW
var allRules = [
{ hostname: ["agar.io"],
scriptUriRe: /^http:\/\/agar\.io\/main_out\.js/,
replace: function (m) {
m.removeNewlines()
m.replace("var:allCells",
/(=null;)(\w+)(.hasOwnProperty\(\w+\)?)/,
"$1" + "$v=$2;" + "$2$3",
"$v = {}")
m.replace("var:myCells",
/(case 32:)(\w+)(\.push)/,
"$1" + "$v=$2;" + "$2$3",
"$v = []")
m.replace("var:top",
/case 49:[^:]+?(\w+)=\[];/,
"$&" + "$v=$1;",
"$v = []")
m.replace("var:ws",
/new WebSocket\((\w+)[^;]+?;/,
"$&" + "$v=$1;",
"$v = ''")
m.replace("var:topTeams",
/case 50:(\w+)=\[];/,
"$&" + "$v=$1;",
"$v = []")
var dr = "(\\w+)=\\w+\\.getFloat64\\(\\w+,!0\\);\\w+\\+=8;\\n?"
var dd = 7071.067811865476
m.replace("var:dimensions",
RegExp("case 64:"+dr+dr+dr+dr),
"$&" + "$v = [$1,$2,$3,$4],",
"$v = " + JSON.stringify([-dd,-dd,dd,dd]))
var vr = "(\\w+)=\\w+\\.getFloat32\\(\\w+,!0\\);\\w+\\+=4;"
m.save() &&
m.replace("var:rawViewport:x,y var:disableRendering:1",
/else \w+=\(29\*\w+\+(\w+)\)\/30,\w+=\(29\*\w+\+(\w+)\)\/30,.*?;/,
"$&" + "$v0.x=$1; $v0.y=$2; if($v1)return;") &&
m.replace("var:disableRendering:2 hook:skipCellDraw",
/(\w+:function\(\w+\){)(if\(this\.\w+\(\)\){\+\+this\.[\w$]+;)/,
"$1" + "if($v || $H(this))return;" + "$2") &&
m.replace("var:rawViewport:scale",
/Math\.pow\(Math\.min\(64\/\w+,1\),\.4\)/,
"($v.scale=$&)") &&
m.replace("var:rawViewport:x,y,scale",
RegExp("case 17:"+vr+vr+vr),
"$&" + "$v.x=$1; $v.y=$2; $v.scale=$3;") &&
m.reset_("window.agar.rawViewport = {x:0,y:0,scale:1};" +
"window.agar.disableRendering = false;") ||
m.restore()
m.replace("reset",
/new WebSocket\(\w+[^;]+?;/,
"$&" + m.reset)
m.replace("property:scale",
/function \w+\(\w+\){\w+\.preventDefault\(\);[^;]+;1>(\w+)&&\(\1=1\)/,
`;${makeProperty("scale", "$1")};$&`)
m.replace("var:minScale",
/;1>(\w+)&&\(\1=1\)/,
";$v>$1 && ($1=$v)",
"$v = 1")
m.replace("var:region",
/console\.log\("Find "\+(\w+\+\w+)\);/,
"$&" + "$v=$1;",
"$v = ''")
m.replace("cellProperty:isVirus",
/((\w+)=!!\(\w+&1\)[\s\S]{0,400})((\w+).(\w+)=\2;)/,
"$1$4.isVirus=$3")
m.replace("var:dommousescroll",
/("DOMMouseScroll",)(\w+),/,
"$1($v=$2),")
m.replace("var:skinF hook:cellSkin",
/(\w+.fill\(\))(;null!=(\w+))/,
"$1;" +
"if($v)$3 = $v(this,$3);" +
"if($h)$3 = $h(this,$3);" +
"$2");
/*m.replace("bigSkin",
/(null!=(\w+)&&\((\w+)\.save\(\),)(\3\.clip\(\),\w+=)(Math\.max\(this\.size,this\.\w+\))/,
"$1" + "$2.big||" + "$4" + "($2.big?2:1)*" + "$5")*/
m.replace("hook:afterCellStroke",
/\((\w+)\.strokeStyle="#000000",\1\.globalAlpha\*=\.1,\1\.stroke\(\)\);\1\.globalAlpha=1;/,
"$&" + "$H(this);")
m.replace("var:showStartupBg",
/\w+\?\(\w\.globalAlpha=\w+,/,
"$v && $&",
"$v = true")
var vAlive = /\((\w+)\[(\w+)\]==this\){\1\.splice\(\2,1\);/.exec(m.text)
var vEaten = /0<this\.[$\w]+&&(\w+)\.push\(this\)}/.exec(m.text)
!vAlive && console.error("Expose: can't find vAlive")
!vEaten && console.error("Expose: can't find vEaten")
if (vAlive && vEaten)
m.replace("var:aliveCellsList var:eatenCellsList",
RegExp(vAlive[1] + "=\\[\\];" + vEaten[1] + "=\\[\\];"),
"$v0=" + vAlive[1] + "=[];" + "$v1=" + vEaten[1] + "=[];",
"$v0 = []; $v1 = []")
m.replace("hook:drawScore",
/(;(\w+)=Math\.max\(\2,(\w+\(\))\);)0!=\2&&/,
"$1($H($3))||0!=$2&&")
m.replace("hook:beforeTransform hook:beforeDraw var:drawScale",
/(\w+)\.save\(\);\1\.translate\((\w+\/2,\w+\/2)\);\1\.scale\((\w+),\3\);\1\.translate\((-\w+,-\w+)\);/,
"$v = $3;$H0($1,$2,$3,$4);" + "$&" + "$H1($1,$2,$3,$4);",
"$v = 1")
m.replace("hook:afterDraw",
/(\w+)\.restore\(\);(\w+)&&\2\.width&&\1\.drawImage/,
"$H();" + "$&")
m.replace("hook:cellColor",
/(\w+=)this\.color;/,
"$1 ($h && $h(this, this.color) || this.color);")
m.replace("var:drawGrid",
/(\w+)\.globalAlpha=(\.2\*\w+);/,
"if(!$v)return;" + "$&",
"$v = true")
m.replace("hook:drawCellMass",
/&&\((\w+\|\|0==\w+\.length&&\(!this\.\w+\|\|this\.\w+\)&&20<this\.size)\)&&/,
"&&( $h ? $h(this,$1) : ($1) )&&")
m.replace("hook:cellMassText",
/(\.\w+)(\(~~\(this\.size\*this\.size\/100\)\))/,
"$1( $h ? $h(this,$2) : $2 )")
m.replace("hook:cellMassTextScale",
/(\.\w+)\((this\.\w+\(\))\)([\s\S]{0,1000})\1\(\2\/2\)/,
"$1($2)$3$1( $h ? $h(this,$2/2) : ($2/2) )")
var template = (key,n) =>
`this\\.${key}=\\w+\\*\\(this\\.(\\w+)-this\\.(\\w+)\\)\\+this\\.\\${n};`
var re = new RegExp(template('x', 2) + template('y', 4) + template('size', 6))
var match = re.exec(m.text)
if (match) {
m.cellProp.nx = match[1]
m.cellProp.ny = match[3]
m.cellProp.nSize = match[5]
} else
console.error("Expose: cellProp:x,y,size search failed!")
}},
]
function makeProperty(name, varname) {
return "'" + name + "' in window.agar || " +
"Object.defineProperty( window.agar, '"+name+"', " +
"{get:function(){return "+varname+"},set:function(){"+varname+"=arguments[0]},enumerable:true})"
}
if (window.top == window.self) {
if (document.readyState !== 'loading')
return console.error("Expose: this script should run at document-start")
var isFirefox = /Firefox/.test(navigator.userAgent)
// Stage 1: Find corresponding rule
var rules
for (var i = 0; i < allRules.length; i++)
if (allRules[i].hostname.indexOf(window.location.hostname) !== -1) {
rules = allRules[i]
break
}
if (!rules)
return console.error("Expose: cant find corresponding rule")
// Stage 2: Search for `main_out.js`
if (isFirefox) {
function bse_listener(e) { tryReplace(e.target, e) }
window.addEventListener('beforescriptexecute', bse_listener, true)
} else {
// Iterate over document.head child elements and look for `main_out.js`
for (var i = 0; i < document.head.childNodes.length; i++)
if (tryReplace(document.head.childNodes[i]))
return
// If there are no desired element in document.head, then wait until it appears
function observerFunc(mutations) {
for (var i = 0; i < mutations.length; i++) {
var addedNodes = mutations[i].addedNodes
for (var j = 0; j < addedNodes.length; j++)
if (tryReplace(addedNodes[j]))
return observer.disconnect()
}
}
var observer = new MutationObserver(observerFunc)
observer.observe(document.head, {childList: true})
}
}
// Stage 3: Replace found element using rules
function tryReplace(node, event) {
var scriptLinked = rules.scriptUriRe && rules.scriptUriRe.test(node.src)
var scriptEmbedded = rules.scriptTextRe && rules.scriptTextRe.test(node.textContent)
if (node.tagName != "SCRIPT" || (!scriptLinked && !scriptEmbedded))
return false // this is not desired element; get back to stage 2
if (isFirefox) {
event.preventDefault()
window.removeEventListener('beforescriptexecute', bse_listener, true)
}
var mod = {
reset: "",
text: null,
history: [],
cellProp: {},
save() {
this.history.push({reset:this.reset, text:this.text})
return true
},
restore() {
var state = this.history.pop()
this.reset = state.reset
this.text = state.text
return true
},
reset_(reset) {
this.reset += reset
return true
},
replace(what, from, to, reset) {
var vars = [], hooks = []
what.split(" ").forEach((x) => {
x = x.split(":")
x[0] === "var" && vars.push(x[1])
x[0] === "hook" && hooks.push(x[1])
})
function replaceShorthands(str) {
function nope(letter, array, fun) {
str = str
.split(new RegExp('\\$' + letter + '([0-9]?)'))
.map((v,n) => n%2 ? fun(array[v||0]) : v)
.join("")
}
nope('v', vars, (name) => "window.agar." + name)
nope('h', hooks, (name) => "window.agar.hooks." + name)
nope('H', hooks, (name) =>
"window.agar.hooks." + name + "&&" +
"window.agar.hooks." + name)
return str
}
var newText = this.text.replace(from, replaceShorthands(to))
if(newText === this.text) {
console.error("Expose: `" + what + "` replacement failed!")
return false
} else {
this.text = newText
if (reset)
this.reset += replaceShorthands(reset) + ";"
return true
}
},
removeNewlines() {
this.text = this.text.replace(/([,\/])\n/mg, "$1")
},
get: function() {
var cellProp = JSON.stringify(this.cellProp)
return `window.agar={hooks:{},cellProp:${cellProp}};` +
this.reset + this.text
}
}
if (scriptEmbedded) {
mod.text = node.textContent
rules.replace(mod)
if (isFirefox) {
document.head.removeChild(node)
var script = document.createElement("script")
script.textContent = mod.get()
document.head.appendChild(script)
} else {
node.textContent = mod.get()
}
console.log("Expose: replacement done")
} else {
document.head.removeChild(node)
var request = new XMLHttpRequest()
request.onload = function() {
var script = document.createElement("script")
mod.text = this.responseText
rules.replace(mod)
script.textContent = mod.get()
// `main_out.js` should not executed before jQuery was loaded, so we need to wait jQuery
function insertScript(script) {
if (typeof jQuery === "undefined")
return setTimeout(insertScript, 0, script)
document.head.appendChild(script)
console.log("Expose: replacement done")
}
insertScript(script)
}
request.onerror = function() { console.error("Expose: response was null") }
request.open("get", node.src, true)
request.send()
}
return true
}
Lines 260-267 for easier debugging purposes:
"Object.defineProperty( window.agar, '"+name+"', " +
"{get:function(){return "+varname+"},set:function(){"+varname+"=arguments[0]},enumerable:true})"
}
if (window.top == window.self) {
if (document.readyState !== 'loading')
return console.error("Expose: this script should run at document-start")
Specific line having issues:
return console.error("Expose: this script should run at document-start")
UPDATE:
New issue. Uncaught SyntaxError: Illegal return statement engine.js:282
Lines 281-282 for debugging purposes:
if (!rules)
return console.error("Expose: cant find corresponding rule")
UPDATE 2:
This is my final issue. And this whole thing will be resolved.
It looks like its another return error. But i do not understand how to properly return this part.
Heres the error but its basically the same.
Uncaught SyntaxError: Illegal return statement engine.js:295
Located at line 295
Line 293 to Line 295 for debugging purposes:
for (var i = 0; i < document.head.childNodes.length; i++)
if (tryReplace(document.head.childNodes[i])){
return
}

here's a fix for the block of code that's causing the error
if (window.top == window.self) {
if (document.readyState !== 'loading') {
// don't return
console.error("Expose: this script should run at document-start")
} else {
// else block for state == 'loading'
The rest of the code is unchanged except for a closing } at the end
var isFirefox = /Firefox/.test(navigator.userAgent)
// Stage 1: Find corresponding rule
var rules
for (var i = 0; i < allRules.length; i++)
if (allRules[i].hostname.indexOf(window.location.hostname) !== -1) {
rules = allRules[i]
break
}
if (!rules)
return console.error("Expose: cant find corresponding rule")
// Stage 2: Search for `main_out.js`
if (isFirefox) {
function bse_listener(e) {
tryReplace(e.target, e)
}
window.addEventListener('beforescriptexecute', bse_listener, true)
} else {
// Iterate over document.head child elements and look for `main_out.js`
for (var i = 0; i < document.head.childNodes.length; i++)
if (tryReplace(document.head.childNodes[i]))
return
// If there are no desired element in document.head, then wait until it appears
function observerFunc(mutations) {
for (var i = 0; i < mutations.length; i++) {
var addedNodes = mutations[i].addedNodes
for (var j = 0; j < addedNodes.length; j++)
if (tryReplace(addedNodes[j]))
return observer.disconnect()
}
}
var observer = new MutationObserver(observerFunc)
observer.observe(document.head, {
childList: true
})
}
} // added this closing }
}

Calling sub functions

This is a program to find the nth fibonacci number.
var fib = (function() {
var save = [];
var i = 0;
return {
"getNum": function(input) {
this.input = input;
if (input === 0) {
console.log("Invalid input");
}
save[i] = i;
save[i + 1] = i + 1;
save[i + 2] = i + 1;
i = 2;
for (i >= 2; i < input; i = i + 1) {
save[i + 1] = save[i] + save[i - 1];
}
console.log(save[i - 1]);
}
}
}());
fib.getNum(4);
My question is when I implement this problem in the following way, it doesn't work. I understand this is because I am not calling the sub-functions and only calling the main function. Is there a better pattern we can use that will keep the code organised and we won't have to make calls to so many functions?
var fib = (function() {
var save = [];
var i = 0;
return {
"getNum": function(input) {
this.input = input;
function valid() {
if (input === 0) {
console.log("Invalid input");
}
}
function config() {
save[i] = i;
save[i + 1] = i + 1;
save[i + 2] = i + 1;
i = 2;
}
function nthNum() {
for (i >= 2; i < input; i = i + 1) {
save[i + 1] = save[i] + save[i - 1];
}
console.log(save[i - 1]);
}
}
}
}());
fib.getNum(4);

You can think of using closure to create private and public functions.If you see the below code only _getNum function is exposed.
var fib = (function() {
var save = [];
save[0] = 0;
save[1] = 1;
var i = 0;
//This will validate the number
// This function can be avoided and make _getNum do the same
function _valid(input){
console.log("Method Executing:_valid");
input === 0 ? console.log('Invalid Input') : _nthNum(input);
}
// Will calualte the series.
// This is a private function
function _nthNum(input) {
console.log('Method Executing:_nthNum');
for (i = 2; i<=input; i++) {
save[i] = save[i-2] + save[i - 1];
}
console.log(save.pop());
}
// Private Function
function _getNum(input){
console.log("Method Executing :_getNum" ,input);
_valid(input);
}
//Expose the private function
return {
getNum :_getNum // Expose _getNum
}
}());
fib.getNum(0);
fib.getNum(4);
fib.getNum(7);
WORKING COPY

My suggestion:
var Fibonacci = (function() {
var _Fibonacci = {
// set initial values
result: [0, 1, 1],
input: 0,
// main function
find: function (number) {
this.input = number;
if (this.isValid()) {
this.calculate();
return this.result.pop();
}
return 'Invalid input';
},
// sub functions
isValid: function () {
return this.input != 0
},
calculate: function () {
for (var i=2; i<this.input; i++) { // fix your code here
this.result[i+1] = this.result[i] + this.result[i-1];
}
}
};
// return the main function
return _Fibonacci.find.bind(_Fibonacci);
}());
console.log(
Fibonacci(0),
Fibonacci(4),
Fibonacci(6)
);

Not getting response on simulator when i call web service using java script

Hi i am using phone gap technology for blackberry development . i want to call soap based xml .when i run html page on internet explore web service response will come but when i run in simulator or device no response will come.Please help.thanks in advance .i used java script.
/*
Javascript "SOAP Client" library
#version: 2.1 - 2006.09.08
#author: Matteo Casati - http://www.guru4.net/
*/
var arr = new Array();
var arrayIndex;
arrayIndex = 0;
function SOAPClientParameters()
{
var _pl = new Array();
this.add = function(name, value)
{
_pl[name] = value;
return this;
}
this.toXml = function()
{
var xml = "";
for(var p in _pl)
xml += "<" + p + ">" + SOAPClientParameters._serialize(_pl[p]) + "</" + p + ">";
return xml;
}
}
SOAPClientParameters._serialize = function(o)
{
var s = "";
switch(typeof(o))
{
case "string":
s += o.replace(/&/g, "&").replace(/</g, "<").replace(/>/g, ">"); break;
case "number":
case "boolean":
s += o.toString(); break;
case "object":
// Date
if(o.constructor.toString().indexOf("function Date()") > -1)
{
var year = o.getFullYear().toString();
var month = (o.getMonth() + 1).toString(); month = (month.length == 1) ? "0" + month : month;
var date = o.getDate().toString(); date = (date.length == 1) ? "0" + date : date;
var hours = o.getHours().toString(); hours = (hours.length == 1) ? "0" + hours : hours;
var minutes = o.getMinutes().toString(); minutes = (minutes.length == 1) ? "0" + minutes : minutes;
var seconds = o.getSeconds().toString(); seconds = (seconds.length == 1) ? "0" + seconds : seconds;
var milliseconds = o.getMilliseconds().toString();
var tzminutes = Math.abs(o.getTimezoneOffset());
var tzhours = 0;
while(tzminutes >= 60)
{
tzhours++;
tzminutes -= 60;
}
tzminutes = (tzminutes.toString().length == 1) ? "0" + tzminutes.toString() : tzminutes.toString();
tzhours = (tzhours.toString().length == 1) ? "0" + tzhours.toString() : tzhours.toString();
var timezone = ((o.getTimezoneOffset() < 0) ? "+" : "-") + tzhours + ":" + tzminutes;
s += year + "-" + month + "-" + date + "T" + hours + ":" + minutes + ":" + seconds + "." + milliseconds + timezone;
}
// Array
else if(o.constructor.toString().indexOf("function Array()") > -1)
{
for(var p in o)
{
if(!isNaN(p)) // linear array
{
(/function\s+(\w*)\s*\(/ig).exec(o[p].constructor.toString());
var type = RegExp.$1;
switch(type)
{
case "":
type = typeof(o[p]);
case "String":
type = "string"; break;
case "Number":
type = "int"; break;
case "Boolean":
type = "bool"; break;
case "Date":
type = "DateTime"; break;
}
s += "<" + type + ">" + SOAPClientParameters._serialize(o[p]) + "</" + type + ">"
}
else // associative array
s += "<" + p + ">" + SOAPClientParameters._serialize(o[p]) + "</" + p + ">"
}
}
// Object or custom function
else
for(var p in o)
s += "<" + p + ">" + SOAPClientParameters._serialize(o[p]) + "</" + p + ">";
break;
default:
throw new Error(500, "SOAPClientParameters: type '" + typeof(o) + "' is not supported");
}
return s;
}
function SOAPClient() {}
SOAPClient.invoke = function(url, method, parameters, async, callback)
{
if(async)
SOAPClient._loadWsdl(url, method, parameters, async, callback);
else
return SOAPClient._loadWsdl(url, method, parameters, async, callback);
}
// private: wsdl cache
SOAPClient_cacheWsdl = new Array();
// private: invoke async
SOAPClient._loadWsdl = function(url, method, parameters, async, callback)
{
// load from cache?
var wsdl = SOAPClient_cacheWsdl[url];
if(wsdl + "" != "" && wsdl + "" != "undefined")
return SOAPClient._sendSoapRequest(url, method, parameters, async, callback, wsdl);
// get wsdl
var xmlHttp = SOAPClient._getXmlHttp();
xmlHttp.open("GET", url + "?wsdl", async);
if(async)
{
xmlHttp.onreadystatechange = function()
{
if(xmlHttp.readyState == 4)
SOAPClient._onLoadWsdl(url, method, parameters, async, callback, xmlHttp);
}
}
xmlHttp.send(null);
if (!async)
return SOAPClient._onLoadWsdl(url, method, parameters, async, callback, xmlHttp);
}
SOAPClient._onLoadWsdl = function(url, method, parameters, async, callback, req)
{
var wsdl = req.responseXML;
SOAPClient_cacheWsdl[url] = wsdl; // save a copy in cache
return SOAPClient._sendSoapRequest(url, method, parameters, async, callback, wsdl);
}
SOAPClient._sendSoapRequest = function(url, method, parameters, async, callback, wsdl)
{
// get namespace
var ns = (wsdl.documentElement.attributes["targetNamespace"] + "" == "undefined") ? wsdl.documentElement.attributes.getNamedItem("targetNamespace").nodeValue : wsdl.documentElement.attributes["targetNamespace"].value;
alert(ns);
// build SOAP request
var sr =
"<?xml version=\"1.0\" encoding=\"utf-8\"?>" +
"<soap:Envelope " +
"xmlns:xsi=\"http://www.w3.org/2001/XMLSchema-instance\" " +
"xmlns:xsd=\"http://www.w3.org/2001/XMLSchema\" " +
"xmlns:soap=\"http://schemas.xmlsoap.org/soap/envelope/\">" +
"<soap:Body>" +
"<" + method + " xmlns=\"" + ns + "\">" +
parameters.toXml() +
"</" + method + "></soap:Body></soap:Envelope>";
// send request
var xmlHttp = SOAPClient._getXmlHttp();
xmlHttp.open("POST", url, async);
var soapaction = ((ns.lastIndexOf("/") != ns.length - 1) ? ns + "/" : ns) + method;
xmlHttp.setRequestHeader("SOAPAction", soapaction);
xmlHttp.setRequestHeader("Content-Type", "text/xml; charset=utf-8");
if(async)
{
xmlHttp.onreadystatechange = function()
{
if(xmlHttp.readyState == 4)
SOAPClient._onSendSoapRequest(method, async, callback, wsdl, xmlHttp);
}
}
xmlHttp.send(sr);
if (!async)
return SOAPClient._onSendSoapRequest(method, async, callback, wsdl, xmlHttp);
}
SOAPClient._onSendSoapRequest = function(method, async, callback, wsdl, req)
{
var o = null;
var nd = SOAPClient._getElementsByTagName(req.responseXML, method + "Response");
alert("ND " +nd);
if(nd.length == 0)
{
if(req.responseXML.getElementsByTagName("faultcode").length > 0)
{
if(async || callback)
o = new Error(500, req.responseXML.getElementsByTagName("faultstring")[0].childNodes[0].nodeValue);
else
throw new Error(500, req.responseXML.getElementsByTagName("faultstring")[0].childNodes[0].nodeValue);
} else {
}
}
else{
o = SOAPClient._soapresult2object(nd[0], wsdl);
}
if(callback){
callback(arr);
}
if(!async)
return o;
}
SOAPClient._soapresult2object = function(node, wsdl)
{
var wsdlTypes = SOAPClient._getTypesFromWsdl(wsdl);
return SOAPClient._node2object(node, wsdlTypes);
}
SOAPClient._node2object = function(node, wsdlTypes)
{
if(node == null)
{
return null;
}
// text node
if(node.nodeType == 3 || node.nodeType == 4)
return SOAPClient._extractValue(node, wsdlTypes);
// leaf node
if (node.childNodes.length == 1 && (node.childNodes[0].nodeType == 3 || node.childNodes[0].nodeType == 4))
return SOAPClient._node2object(node.childNodes[0], wsdlTypes);
var isarray = SOAPClient._getTypeFromWsdl(node.nodeName, wsdlTypes).toLowerCase().indexOf("arrayof") != -1;
// object node
if(!isarray)
{
var obj = null;
if(node.hasChildNodes())
{
obj = new Object();
for(var i = 0; i < node.childNodes.length ; i++)
{
var p = SOAPClient._node2object(node.childNodes[i], wsdlTypes);
if((node.childNodes[i].nodeName.toLowerCase().indexOf("Return") == -1) && (node.childNodes[i].nodeName.toLowerCase().indexOf("Response") == -1))
{
obj[node.childNodes[i].nodeName] = p;
}
}
arr[arrayIndex++] = obj;
}
return obj;
}
// list node
else
{
//create node ref
var l = new Array();
for(var i = 0; i < node.childNodes.length; i++)
l[l.length] = SOAPClient._node2object(node.childNodes[i], wsdlTypes);
return l;
}
return null;
}
SOAPClient._extractValue = function(node, wsdlTypes)
{
var value = node.nodeValue;
switch(SOAPClient._getTypeFromWsdl(node.parentNode.nodeName, wsdlTypes).toLowerCase())
{
default:
case "s:string":
return (value != null) ? value + "" : "";
case "s:boolean":
return value + "" == "true";
case "s:int":
case "s:long":
return (value != null) ? parseInt(value + "", 10) : 0;
case "s:double":
return (value != null) ? parseFloat(value + "") : 0;
case "s:datetime":
if(value == null)
return null;
else
{
value = value + "";
value = value.substring(0, (value.lastIndexOf(".") == -1 ? value.length : value.lastIndexOf(".")));
value = value.replace(/T/gi," ");
value = value.replace(/-/gi,"/");
var d = new Date();
d.setTime(Date.parse(value));
return d;
}
}
}
SOAPClient._getTypesFromWsdl = function(wsdl)
{
var wsdlTypes = new Array();
// IE
var ell = wsdl.getElementsByTagName("s:element");
var useNamedItem = true;
// MOZ
if(ell.length == 0)
{
ell = wsdl.getElementsByTagName("element");
useNamedItem = false;
}
for(var i = 0; i < ell.length; i++)
{
if(useNamedItem)
{
if(ell[i].attributes.getNamedItem("name") != null && ell[i].attributes.getNamedItem("type") != null)
wsdlTypes[ell[i].attributes.getNamedItem("name").nodeValue] = ell[i].attributes.getNamedItem("type").nodeValue;
}
else
{
if(ell[i].attributes["name"] != null && ell[i].attributes["type"] != null)
wsdlTypes[ell[i].attributes["name"].value] = ell[i].attributes["type"].value;
}
}
return wsdlTypes;
}
SOAPClient._getTypeFromWsdl = function(elementname, wsdlTypes)
{
var type = wsdlTypes[elementname] + "";
return (type == "undefined") ? "" : type;
}
// private: utils
SOAPClient._getElementsByTagName = function(document, tagName)
{
try
{
// trying to get node omitting any namespaces (latest versions of MSXML.XMLDocument)
return document.selectNodes(".//*[local-name()=\""+ tagName +"\"]");
}
catch (ex) {}
// old XML parser support
return document.getElementsByTagName(tagName);
}
// private: xmlhttp factory
SOAPClient._getXmlHttp = function()
{
try
{
if(window.XMLHttpRequest)
{
var req = new XMLHttpRequest();
// some versions of Moz do not support the readyState property and the onreadystate event so we patch it!
if(req.readyState == null)
{
req.readyState = 1;
req.addEventListener("load",
function()
{
req.readyState = 4;
if(typeof req.onreadystatechange == "function")
req.onreadystatechange();
},
false);
}
return req;
}
if(window.ActiveXObject)
return new ActiveXObject(SOAPClient._getXmlHttpProgID());
}
catch (ex) {}
throw new Error("Your browser does not support XmlHttp objects");
}
SOAPClient._getXmlHttpProgID = function()
{
if(SOAPClient._getXmlHttpProgID.progid)
return SOAPClient._getXmlHttpProgID.progid;
var progids = ["Msxml2.XMLHTTP.5.0", "Msxml2.XMLHTTP.4.0", "MSXML2.XMLHTTP.3.0", "MSXML2.XMLHTTP", "Microsoft.XMLHTTP"];
var o;
for(var i = 0; i < progids.length; i++)
{
try
{
o = new ActiveXObject(progids[i]);
return SOAPClient._getXmlHttpProgID.progid = progids[i];
}
catch (ex) {};
}
throw new Error("Could not find an installed XML parser");
}
xmlParsingDataReturn=function(){
return arr;
}

As a WebWorks app, you are required to whitelist any external domains you will be accessing through your app. Since this works on a computer's browser but not on an actual device or on the simulator, it may be an issue with the config file. See the PhoneGap site for more info on whitelisting.