PHP Exercises: Call a given function only once
PHP: Exercise-101 with Solution
Write a PHP program to call a given function only once.
Sample Solution: -
PHP Code:
<?php
//Licence: https://bit.ly/2CFA5XY
function once($function)
{
return function (...$args) use ($function) {
static $called = false;
if ($called) {
return;
}
$called = true;
return $function(...$args);
};
}
$add = function ($a, $b) {
return $a + $b;
};
$once = once($add);
var_dump($once(10, 5));
var_dump($once(20, 10));
?>
Sample Output:
int(15) NULL
Flowchart:

PHP Code Editor:
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Previous:Write a PHP program to curry a function to take arguments in multiple calls.
Next: Write a PHP program to capture a variable number of arguments to a given function.
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PHP: Tips of the Day
Returns all elements in an array except for the first one
Example:
<?php function tips_tail($items) { return count($items) > 1 ? array_slice($items, 1) : $items; } print_r(tips_tail([1, 5, 7])); ?>
Output:
Array ( [0] => 5 [1] => 7 )
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