mec0825/safe-invoke

safely call function to avoid "&&" hell

safe-invoke

Tiny function used to avoid "&&" hell.

Install

# use yarn
yarn add safe-invoke

# use npm
npm i --save safe-invoke

How to use

Suppose we have an object like this.

let age = {
    muv: {
        luv: [
            {
                extra: (...) => {...}
            },
            {
                unlimited: (...) => {...}
            },
            {
                alternative: (...) => {...}
            }
        ]
    }
};

If we want to call the function extra, unlimited, alternative safely.

Original

age
    && age.muv
    && age.muv.luv
    && age.muv.luv[0]
    && typeof age.muv.luv[0].extra === 'function'
    && age.muv.luv[0].extra();

age
    && age.muv
    && age.muv.luv
    && age.muv.luv[1]
    && typeof age.muv.luv[1].unlimited === 'function'
    && age.muv.luv[1].unlimited('オルタネイティヴ5');

age
    && age.muv
    && age.muv.luv
    && age.muv.luv[2]
    && typeof age.muv.luv[2].alternative === 'function'
    && age.muv.luv[2].alternative('オルタネイティヴ4', '桜花作戦');

Now we can write this way.

import safeInvoke from 'safe-invoke';

safeInvoke(age, 'muv.luv.0.extra');
safeInvoke(age, 'muv.luv.1.unlimited', 'オルタネイティヴ5');
safeInvoke(age, 'muv.luv.2.alternative', 'オルタネイティヴ4', '桜花作戦');

Tips

If key of object contains . self, we should change second argument (path) with array of string like below.

let obj = {
    'A.I.Channel': () => console.log('kizuna ai'),
    'A': {'I': {'Channel': () => console.log('ban')}}
};

safeInvoke(obj, ['A.I.Channel']);
// out: 'kizuna ai'

safeInvoke(obj, 'A.I.Channel');
// or
safeInvoke(obj, ['A', 'I', 'Channel']);
// out: ban

License

MIT