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From: Thomas 'PointedEars' Lahn <PointedEars@web.de>
Newsgroups: comp.lang.javascript
Subject: Re: Find object in array
Date: Mon, 17 Jul 2017 01:30:39 +0200
Organization: PointedEars Software (PES)
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Andrew Poulos wrote:

> On 16/07/2017 7:00 PM, Andrew Poulos wrote:
>> The server returns a string which I parse. It becomes an array of
>> "simple" objects eg.
>> {
>>    "id":1,
>>    "colour": "#fff",
>>    "width": 320,
>>    "height":240
>> }
>> 
>> To find an object with a specific "id" I use a for loop on the array.
>> This is ok but now the arrays I'm getting contain 10s of objects. What
>> better way can I use to find a specific object?
> 
> Doh, I just realised that I can use filter.
> 
> On a related question would it be "faster" to use a for loop, instead of
> multiple filters, if I needed to find a number of objects?

You would not need multiple .filter() calls to find a number of objects.

As to whether .filter() would be faster than a “for” loop, you should test 
it.  A “for” loop should be faster, because it does not incur performance 
costs for calling the function and resolving identifiers along a longer 
scope chain.

BTW, this wheel has been invented before, and it has been called “Language-
Integrated Query (LINQ)”.  Also, my JSX:array.js:jsx.array.createFilter() 
helps you generate a filter callback for filtering objects.

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