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Merge or concatenate arrays

suggest change 
$fruit1 = ['apples', 'pears'];
$fruit2 = ['bananas', 'oranges'];

$all_of_fruits = array_merge($fruit1, $fruit2);
// now value of $all_of_fruits is [0 => 'apples', 1 => 'pears', 2 => 'bananas', 3 => 'oranges']

Note that array_merge will change numeric indexes, but overwrite string indexes 

$fruit1 = ['one' => 'apples',  'two' => 'pears'];
$fruit2 = ['one' => 'bananas', 'two' => 'oranges'];

$all_of_fruits = array_merge($fruit1, $fruit2);
// now value of $all_of_fruits is ['one' => 'bananas', 'two' => 'oranges']

array_merge overwrites the values of the first array with the values of the second array, if it cannot renumber the index.

You can use the \+ operator to merge two arrays in a way that the values of the first array never get overwritten, but it does not renumber numeric indexes, so you lose values of arrays that have an index that is also used in the first array. 

$fruit1 = ['one' => 'apples',  'two' => 'pears'];
$fruit2 = ['one' => 'bananas', 'two' => 'oranges'];

$all_of_fruits = $fruit1 + $fruit2;
// now value of $all_of_fruits is ['one' => 'apples', 'two' => 'pears']

$fruit1 = ['apples', 'pears'];
$fruit2 = ['bananas', 'oranges'];

$all_of_fruits = $fruit1 + $fruit2;
// now value of $all_of_fruits is [0 => 'apples', 1 => 'pears']
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Arrays:
* Arrays
* Initializing an Array
* Applying a function to each element of an array
* Check if key exists
* Validating the array type
* Iterating multiple arrays together
* Filtering an array
* Removing elements from an array
* Creating an array of variables
* Checking if a value exists in array
* Sorting an Array
* Splitting a string by separators
* Array intersection
* Adding element to start of array
* Merge or concatenate arrays
* ArrayAccess and Iterator Interfaces
* Whitelist only some array keys
* Imploding an array into string
* Split array into chunks
* Exchange values with keys
* Combining two arrays keys from one values from another
* array reduce
* Destructuring arrays using list
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0 Getting started
1 Variables
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39 Contributing to PHP Manual
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84 Outputting the value of a variable
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87 MongoDB
88 Manipulating an array
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107 How to break down an URL
108 PSR
109 Contributors