Reflect.apply()

BaselineWidely available

This feature is well established and works across many devices and browser versions. It’s been available across browsers since September 2016.

TheReflect.apply() static method calls a target function with arguments as specified.

Try it

console.log(Reflect.apply(Math.floor, undefined, [1.75]));// Expected output: 1console.log(  Reflect.apply(String.fromCharCode, undefined, [104, 101, 108, 108, 111]),);// Expected output: "hello"console.log(  Reflect.apply(RegExp.prototype.exec, /ab/, ["confabulation"]).index,);// Expected output: 4console.log(Reflect.apply("".charAt, "ponies", [3]));// Expected output: "i"

Syntax

Reflect.apply(target, thisArgument, argumentsList)

Parameters

target: The target function to call.
thisArgument: The value ofthis provided for the call totarget.
argumentsList: Anarray-like object specifying the arguments with whichtarget should be called.

Return value

The result of calling the giventarget function with the specifiedthis value and arguments.

Exceptions

TypeError: Thrown iftarget is not a function orargumentsList is not an object.

Description

Reflect.apply() provides the reflective semantic of a function call. That is,Reflect.apply(target, thisArgument, argumentsList) is semantically equivalent to:

Math.floor.apply(null, [1.75]);Reflect.apply(Math.floor, null, [1.75]);

The only differences are:

Reflect.apply() takes the function to call as thetarget parameter instead of thethis context.
Reflect.apply() throws ifargumentsList is omitted instead of defaulting to calling with no parameters.

Reflect.apply() invokes the[[Call]]object internal method oftarget.

Examples

Using Reflect.apply()

Reflect.apply(Math.floor, undefined, [1.75]);// 1;Reflect.apply(String.fromCharCode, undefined, [104, 101, 108, 108, 111]);// "hello"Reflect.apply(RegExp.prototype.exec, /ab/, ["confabulation"]).index;// 4Reflect.apply("".charAt, "ponies", [3]);// "i"