is-bound-func

Check if given function is bound or not.

npm install is-bound-func

API

index.d.ts

isBoundFunc<T extends Function>(fn: T, chkLevel = 2)

demo

const isBoundFunc = require('is-bound-func')
import isBoundFunc from 'is-bound-func';
import * as isBoundFunc from 'is-bound-func';

demo.ts

[
    () => {},
    function (){},
    function a(){},
    parseInt,
    parseInt.bind(null),
].forEach(fn =>
{
    // when fn not bound will return null, else will return a number
 
    console.dir({
        name: fn.name,
        fn,
    });
    console.dir([isBoundFunc(fn), isBoundFunc(fn.bind(null))]);
});

output

{ name: '', fn: [Function] }
[ null, 2 ]
{ name: '', fn: [Function] }
[ null, 2 ]
{ name: 'a', fn: [Function: a] }
[ null, 2 ]
{ name: 'parseInt', fn: [Function: parseInt] }
[ null, 2 ]
{ name: 'bound parseInt', fn: [Function: bound parseInt] }
[ 2, 2 ]