The function returns a new thing with properties that pass the test.

This function does not generate a change.




Argument Type Description
callback closure (required) Closure to execute on each value.

Explanation of the callback argument:

Iterable Arguments Description
thing name, value Iterate over the thing properties. Both name and value are optional.

Return value

A new thing with the properties that pass the test. If no properties pass the test, a empty thing will be returned.


This code shows an example using filter():

user = {name: 'Iris', age: 6};

 * Return a thing with only property age

user.filter(|prop| prop == 'age');

Return value in JSON format

    "age": 6