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What is the logic of bitwise operators on undefined??? var x; console.log(x); // undefined console.log(x^7); // 7 console.log(7^x); // 7 console.log(x|7); // 7 console.log(7|x); // 7 console.log(7&x); // 0 console.log(x&7); // 0 console.log(~x); // -1 console.log(x*2); // NaN console.log(x/2); // NaN console.log(x+2); // NaN console.log(x-2); // NaN I can see some sense in NaN. Because undefined -2 is really 'not a number'. But I do not follow any logic on bitwise operators and undefined. The internal function [ToInt32] is called on all operands for all bitwise operators. Note that ToInt32

Can't a compiler warn (even better if it throws errors) when it notices a statement with undefined/unspecified/implementation-defined behaviour? Probably to flag a statement as error, the standard should say so, but it can warn the coder at least. Is there any technical difficulties in implementing such an option? Or is it merely impossible? Reason I got this question is, in statements like a[i] = ++i; won't it be knowing that the code is trying to reference a variable and modifying it in the same statement, before a sequence point is reached. Alok Singhal It all boils down to Quality of

I have a trouble with angular 2 here. I use service that return promise but when i try to retrive the response i got an error. i was read this this stact question this my code. this is HotelService.ts import { Injectable } from '@angular/core'; import { Http } from '@angular/http'; //rxjs promises cause angular http return observable natively. import 'rxjs/add/operator/toPromise'; @Injectable() export class HotelService { private BASEURL : any = 'http://localhost:8080/hotel/'; constructor(private http: Http) {} load(): Promise<any> { return this.http.get(this.BASEURL + 'api/client/hotel/load')

I am trying to solve a problem that came to my mind lately. Let's say we would want and would know how to make a point in having dynamic getters and setters in javascript, more like those in php (__get, __set). But as javascript does not have a catch-all property the only thing we could do is to provide a list of possible keys and iterate to add getters and setters on those only, and hope none other will ever come. But the problem is not by far solved. So the next approach that came to my mind was to use a nasty hack with try and catch , so anytime a name would be undefined in an object to use

I have some PHP code in a project I'm working on that uses PHP's round function. On my localhost, I don't include any quotes around my mode argument, stating it as just PHP_ROUND_HALF_DOWN. However, when pushing to my server I get the error message: Use of undefined constant PHP_ROUND_HALF_DOWN - assumed 'PHP_ROUND_HALF_DOWN' Warning (2): Wrong parameter count for round() [APP/views/helpers/time_left.php, line 14] Now, when I add the single quotes to the mode argument, the first error goes away, however the "wrong parameter count" remains. I'm calling the function as follows: $days = round((

When a is undefined, then a || 1 will throw an error, but a = a || 1 will not. Isn't that a little bit inconsistent? irb(main):001:0> a NameError: undefined local variable or method 'a' for main:Object from (irb):1 from c:/ruby/bin/irb:12:in '<main>' irb(main):002:0> a || 1 NameError: undefined local variable or method 'a' for main:Object from (irb):2 from c:/ruby/bin/irb:12:in '<main>' irb(main):003:0> a = a || 1 => 1 a Here, you are evaluating a , which isn't defined. Therefore, you get an exception. a || 1 Here, you still have to evaluate a to determine the value of the boolean expression.

This question already has an answer here: static variable link error 2 answers I have no idea why this code isn't working. All the source files compile but when I try to link them the compiler yells at me with an undefined reference error. Here's the code: main.cpp: #include "SDL/SDL.h" #include "Initilize.cpp" int main(int argc, char* args[]) { //Keeps the program looping bool quit = false; SDL_Event exit; //Initilizes, checks for errors if(Initilize::Start() == -1) { SDL_Quit(); } //main program loop while(quit == false) { //checks for events while(SDL_PollEvent(&exit)) { //checks for type

If I have a function like the following: function catchUndefinedFunctionCall( name, arguments ) { alert( name + ' is not defined' ); } and I do something silly like foo( 'bar' ); when foo isn't defined, is there some way I can have my catch function called, with name being 'foo' and arguments being an array containing 'bar'? There is in Mozilla Javascript 1.5 anyway (it's nonstandard). Check this out: var myObj = { foo: function () { alert('foo!'); } , __noSuchMethod__: function (id, args) { alert('Oh no! '+id+' is not here to take care of your parameter/s ('+args+')'); } } myObj.foo(); myObj