David-Sarah Hopwood wrote:
> Mark S. Miller wrote:
>> function isArrayLike(obj) {
>> var len;
>> return !!(obj &&
>> typeof obj === 'object' &&
>> 'length' in obj &&
>> !({}).propertyIsEnumerable.call(obj, 'length') &&
>> (len = obj.length) >>> 0 === len);
>> }
>>
>> Since getting 'length' may have side effects, this is written a bit weird so
>> that this get only happens after earlier tests pass.
>
> If you want to avoid side effects:
>
> function isArrayLike(obj) {
> if (!obj || typeof obj !== 'object') return false;
> var desc = Object.getPropertyDescriptor(obj, 'length');
getOwnPropertyDescriptor, I meant.
> if (desc) {
> var len = desc.value;
> return !desc.enumerable && (len === undefined || len >>> 0 === len);
> }
> }
--
David-Sarah Hopwood ⚥ http://davidsarah.livejournal.com
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