apcu_cas
(PECL apcu >= 4.0.0)
apcu_cas — Updates an old value with a new value
説明
bool apcu_cas
( string
$key
, int $old
, int $new
)
apcu_cas() updates an already existing integer value if the
old parameter matches the currently stored value
with the value of the new parameter.
パラメータ
-
key -
The key of the value being updated.
-
old -
The old value (the value currently stored).
-
new -
The new value to update to.
返り値
成功した場合に TRUE を、失敗した場合に FALSE を返します。
例
例1 apcu_cas() example
<?php
apcu_store('foobar', 2);
echo '$foobar = 2', PHP_EOL;
echo '$foobar == 1 ? 2 : 1 = ', (apcu_cas('foobar', 1, 2) ? 'ok' : 'fail'), PHP_EOL;
echo '$foobar == 2 ? 1 : 2 = ', (apcu_cas('foobar', 2, 1) ? 'ok' : 'fail'), PHP_EOL;
echo '$foobar = ', apcu_fetch('foobar'), PHP_EOL;
echo '$f__bar == 1 ? 2 : 1 = ', (apcu_cas('f__bar', 1, 2) ? 'ok' : 'fail'), PHP_EOL;
apcu_store('perfection', 'xyz');
echo '$perfection == 2 ? 1 : 2 = ', (apcu_cas('perfection', 2, 1) ? 'ok' : 'epic fail'), PHP_EOL;
echo '$foobar = ', apcu_fetch('foobar'), PHP_EOL;
?>
上の例の出力は、 たとえば以下のようになります。
$foobar = 2 $foobar == 1 ? 2 : 1 = fail $foobar == 2 ? 1 : 2 = ok $foobar = 1 $f__bar == 1 ? 2 : 1 = fail $perfection == 2 ? 1 : 2 = epic fail $foobar = 1
参考
- apcu_dec() - Decrease a stored number
- apcu_store() - Cache a variable in the data store
忘却曲線を使ってこの関数を確実に記憶に残す
