object-assign-defined

A tiny, fast and well-tested JavaScript module that works just like Object.assign, but skips assigning undefined values.

Usage

Import the module and use it like this:

import objectAssignDefined from "object-assign-defined";

const result = objectAssignDefined(
  {
    I: 1,
  },
  {
    LIKE: 2,
  },
  {
    TRAINS: undefined,
  }
);

// result is { "I": 1, "LIKE": 2 }

Note that undefined values in source (first argument) won't be vanished:

import objectAssignDefined from "object-assign-defined";

const result = objectAssignDefined(
  {
    I: undefined,
  },
  {
    LIKE: 2,
  },
  {
    TRAINS: 3,
  }
);

// result is { "I": undefined, "LIKE": 2, "TRAINS": 3 }

But you can simply filter undefined values by assigning properties to an empty object, like this:

import objectAssignDefined from "object-assign-defined";

const result = objectAssignDefined({}, { I: undefined });

// result is {}

Licence

MIT © Nikita Savchenko