我有很多函数,它们要么具有数组类型提示,要么使用 is_array()
来检查变量的数组特性.
I have a lot of functions that either have type hinting for arrays or use is_array()
to check the array-ness of a variable.
现在我开始使用可迭代的对象.它们实现 Iterator
或 IteratorAggregate
.如果它们通过类型提示或经过 is_array()
,它们会被作为数组接受吗?
Now I'm starting to use objects that are iterable. They implement Iterator
or IteratorAggregate
. Will these be accepted as arrays if they pass through type hinting, or undergo is_array()
?
如果我必须修改我的代码,是否有一种通用的 is_iterable()
,或者我必须这样做:
If I have to modify my code, is there a generic sort of is_iterable()
, or must I do something like:
if ( is_array($var) OR $var instance_of Iterable OR $var instanceof IteratorAggregate ) { ... }
还有哪些其他可迭代的接口?
What other iterable interfaces are out there?
我想你的意思是 instanceof Iterator
,PHP 没有 Iterable
接口.它确实有一个 Traversable
接口.Iterator
和 IteratorAggregate
都扩展了 Traversable
(并且 AFAIK 他们是唯一这样做的).
I think you mean instanceof Iterator
, PHP doesn't have an Iterable
interface. It does have a Traversable
interface though. Iterator
and IteratorAggregate
both extend Traversable
(and AFAIK they are the only ones to do so).
但是不,实现 Traversable
的对象不会通过 is_array()
检查,也没有内置的 is_iterable()
功能.您可以使用的支票是
But no, objects implementing Traversable
won't pass the is_array()
check, nor there is a built-in is_iterable()
function. A check you could use is
function is_iterable($var) {
return (is_array($var) || $var instanceof Traversable);
}
需要明确的是,所有 php 对象都可以用foreach 进行迭代,但只有一些 实现了Traversable
.因此,提供的 is_iterable
函数不会检测到 foreach 可以处理的所有内容.
To be clear, all php objects can be iterated with foreach, but only some of them implement Traversable
. The presented is_iterable
function will therefore not detect all things that foreach can handle.
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