(PECL ds >= 1.0.0)
Ds\Sequence::reduce โ Reduces the sequence to a single value using a callback function
Reduces the sequence to a single value using a callback function.
callbackcarry
The return value of the previous callback, or initial if
it's the first iteration.
valueThe value of the current iteration.
initial
The initial value of the carry value. Can be null.
The return value of the final callback.
็คบไพ #1 Ds\Sequence::reduce() with initial value example
<?php
$sequence = new \Ds\Vector([1, 2, 3]);
$callback = function($carry, $value) {
return $carry * $value;
};
var_dump($sequence->reduce($callback, 5));
// Iterations:
//
// $carry = $initial = 5
//
// $carry = $carry * 1 = 5
// $carry = $carry * 2 = 10
// $carry = $carry * 3 = 30
?>ไปฅไธ็คบไพ็่พๅบ็ฑปไผผไบ๏ผ
int(30)
็คบไพ #2 Ds\Sequence::reduce() without an initial value example
<?php
$sequence = new \Ds\Vector([1, 2, 3]);
var_dump($sequence->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
?>ไปฅไธ็คบไพ็่พๅบ็ฑปไผผไบ๏ผ
int(21)