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Change all values of an array without a loop construct

Asked 2012-10-02T13:27:31.207
27

I have the following array in php:

$a = [0, 4, 5, 7];

I would like to increment all the values without writing a loop (for, foreach...)

// increment all values
// $a is now array(1, 5, 6, 8)

Is it possible in php?

And by extention, is it possible to call a function on each element and replace that element by the return value of the function?

For example:

$a = doubleValues($a); // array(0, 8, 10, 14)
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1 Answer

66

This is a job for array_map() (which will loop internally):

$a = array(0, 4, 5, 7);
// PHP 5.3+ anonmymous function.
$output = array_map(function($val) { return $val+1; }, $a);

print_r($output);
Array
(
    [0] => 1
    [1] => 5
    [2] => 6
    [3] => 8
)

Edit by OP:

function doubleValues($a) {
  return array_map(function($val) { return $val * 2; }, $a);
}
answered 2012-10-02T13:29:14.233

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