Deque
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Ds\Deque::reduce

(PECL ds >= 1.0.0)

Ds\Deque::reduceReduces the deque to a single value using a callback function.

Description

public mixed Ds\Deque::reduce ( callable $callback [, mixed $initial ] )

Reduces the deque to a single value using a callback function.

Liste de paramètres

callback
mixed callback ( mixed $carry , mixed $value )
carry

The return value of the previous callback, or initial if it's the first iteration.

value

The value of the current iteration.

initial

The initial value of the carry value. Can be NULL.

Valeurs de retour

The return value of the final callback.

Exemples

Exemple #1 Ds\Deque::reduce() with initial value example

<?php
$deque 
= new \Ds\Deque([123]);

$callback = function($carry$value) {
    return 
$carry $value;
};

var_dump($deque->reduce($callback5));

// Iterations:
//
// $carry = $initial = 5
//
// $carry = $carry * 1 =  5
// $carry = $carry * 2 = 10
// $carry = $carry * 3 = 30
?>

L'exemple ci-dessus va afficher quelque chose de similaire à :

int(30)

Exemple #2 Ds\Deque::reduce() without an initial value example

<?php
$deque 
= new \Ds\Deque([123]);

var_dump($deque->reduce(function($carry$value) {
    return 
$carry $value 5;
}));

// Iterations:
//
// $carry = $initial = null
//
// $carry = $carry + 1 + 5 =  6
// $carry = $carry + 2 + 5 = 13
// $carry = $carry + 3 + 5 = 21
?>

L'exemple ci-dessus va afficher quelque chose de similaire à :

int(21)

Deque
PHP Manual