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:

//Licence: https://bit.ly/2CFA5XY

function once($function)
    return function (...$args) use ($function) {
        static $called = false;
        if ($called) {
        $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:



Flowchart: Call a given function only once.

PHP Code Editor:

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PHP: Tips of the Day

Returns all elements in an array except for the first one


function tips_tail($items)
  return count($items) > 1 ? array_slice($items, 1) : $items;

print_r(tips_tail([1, 5, 7]));


    [0] => 5
    [1] => 7