Eloquent JavaScript - Values Variables Control Flow - JSFiddle

the || operator

HTML

<div id="output"></div>

JavaScript

var input = prompt("What is your name?", "");
document.getElementById("output").innerHTML = "Well, hello " + (input || "unknown") + "!";

// the || operator returns the first value, if the value is 'true'/has a value

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Eloquent JavaScript - Values Variables Control Flow

the || operator

HTML

JavaScript

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Join the 4+ million users, and keep the JSFiddle dream alive.

Ad-free

Use pre-released features

Fiddle collections

Private collections and fiddles

Console