WeakMap
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WeakMap::key

(PECL weakref >= 0.2.0)

WeakMap::keyReturns the current key under iteration.

说明

public object WeakMap::key ( void )

Returns the object serving as key in the map, at the current iterating position.

参数

此函数没有参数。

返回值

The object key currently being iterated.


WeakMap
PHP 手册