The when() function is used to callback if the first argument in the given proves to be true. In JavaScript, the array is first converted to a collection and then the function is applied to the collection.
Syntax:
data.when(conditional ,rule)
Parameters: This function accept two parameters as mentioned above and described below:
- rule: This parameter holds the operation rule or the condition to be applied on the collection.
- conditional: This parameter holds the conditional value true or false.
Return value : Return the modified collection list.
Below examples illustrate the when() function in collect.js:
Example 1: Here in this example, we take a collection and then using the when() function modify the collection.
Javascript
// It is used to import collect.js library const collect = require( 'collect.js' ); const collection = collect([0 , 1 , 2]); collection.when( true , items => items.push(3)); console.log(collection.all()); |
Output:
[0 , 1 , 2 , 3]
Example 2: Same as above example but applying a different operation to perform.
Javascript
// It is used to import collect.js library const collect = require( 'collect.js' ); const collection = collect([0 , 1 , 2]); collection.when( true , items => items.put( 'Jason' )); console.log(collection.all()); |
Output:
[ 0, 1, 2, Jason: undefined ]
Reference: https://collect.js.org/api/when.html