The $build helper method will create a new array with the original array's key/value pairs after they have been run through the $callback function. The $callback function should return an array with the new key and value.

The signature for the build helper method is:

build($array, callable $callback)

The following code sample will append is rare to the values in the original array:

 1<?php
 2 
 3use Illuminate\Support\Arr;
 4 
 5$myArray = [
 6    'animal' => 'Araripe Manakin',
 7    'plant' => 'Pineland Wild Petunia'
 8];
 9 
10$myArray = Arr::build($myArray, function($key, $value)
11           {
12                return [$key, $value.' is rare'];
13           });

The final array would be:

1array(2) {
2    ["animal"] "Araripe Manakin is rare"
3    ["plant"]  "Pineland Wild Petunia is rare"
4}

#array_build($array, callable $callback)

The array_build function is a shortcut to calling Arr::build. This function is declared in the global namespace.

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