Filter out an array with null values, underscore

Question

I have this array:

[null, {name:\'John\'}, null, {name:\'Jane\'}]

I want to remove the null values. Is there an easy way to do this with unders

Answer 1

The best solution is to use compact, but the default behaviour of the filter function when you don't include a specific truth test function is to remove falsy values

For example:

_.filter([null, {name:'John'}, null, {name:'Jane'}])

returns a object array without the nulls:

[{name:'John'}, {name:'Jane'}]

Answer 2

This will work for you

Filter

_.filter(arr,function (value) {
    return value!==null;
})

Reject

_.reject(arr,function (value) {
    return value===null;
})

Answer 3

If the array contains either nulls or objects then you could use compact:

var everythingButTheNulls = _.compact(list);

NB compact removes all falsy values so if the array could contain zeros, false etc then they would also be removed.

Could also use reject with the isNull predicate:

var everythingButTheNulls = _.reject(array, _.isNull);

Answer 4

Try using _.without(array, *values) it will remove all the values that you don't need. In your case *values == null

http://underscorejs.org/#without

Answer 5

From underscore documentation

without_.without(array, *values) 
Returns a copy of the array with all instances of the values removed.

So just use this method

var a = [null, {name:'John'}, null, {name:'Jane'}]
a = _.without(a, null);