Function.displayName

The function.displayName property returns the display name of the function.

Description

When defined, the displayName property returns the display name of a function:

function doSomething() {}
console.log(doSomething.displayName); // "undefined"
var popup = function(content) { console.log(content); };
popup.displayName = 'Show Popup';
console.log(popup.displayName); // "Show Popup"

You can define a function with a display name in a function expression:

var object = {
  someMethod: function() {}
};
object.someMethod.displayName = 'someMethod';
console.log(object.someMethod.displayName); // logs "someMethod"
try { someMethod } catch(e) { console.log(e); }
// ReferenceError: someMethod is not defined

You can dynamically change the displayName of a function:

var object = {
  // anonymous
  someMethod: function(value) {
    arguments.callee.displayName = 'someMethod (' + value + ')';
  }
};
console.log(object.someMethod.displayName); // "undefined"
object.someMethod('123')
console.log(object.someMethod.displayName); // "someMethod (123)"

Examples

It is usually preferred by consoles and profilers over func.name to display the name of a function.

By entering the following in a console, it should display as something like "function My Function()":

var a = function() {};
a.displayName = 'My Function';
a; // "function My Function()"

Specifications

Not part of any specification.

Browser compatibility