Prevent unnecessarily collection comparisons

### Type of issue

Typo

### Feedback

Maybe something to add as a performance consideration:

(Related: https://github.com/PowerShell/PowerShell/issues/25720)

---
### Prevent unnecessarily collection comparisons

The [PowerShell comparison operators](https://learn.microsoft.com/powershell/module/microsoft.powershell.core/about/about_comparison_operators) have a nice feature:

> When the left-hand value in the expression is a collection, the operator returns the elements of the collection that match the right-hand value of the expression.

This might come at hand if you want to filter a collection, e.g.:

```powershell
$Collection = 1..99
$Collection -like '*1*' # Yields: 1 10 11 12 13 14 15 16 17 18 19 21 31 41 51 61 71 81 91
```

But in case it is used in a conditional statement or cmdlet that is only supposed to act on the converted [boolean](https://learn.microsoft.com/powershell/module/microsoft.powershell.core/about/about_booleans) result, it might exceed it goal.
Take for example:

```powershell
if ($Collection -like '1*') { 'Found' }
```

At the first item that contains a `"1"`, it is already determined that the result is **true**, yet the *whole* collection is evaluated and than converted to **true**.  Therefore you might consider to work around this feature if it concerns a large collection and an intense comparison.
One way to do this would be:

```PowerShell
if ($Collection.where({ $_ -like '1*' }, 'first')) { 'Found' }
```

In this command line, the [`where` method](https://learn.microsoft.com/powershell/module/microsoft.powershell.core/about/about_arrays#where) will stop evaluating the rest of the collection after the first match is found. For a million items, this specific comparion is about 25 times faster.




### Page URL

https://learn.microsoft.com/en-us/powershell/scripting/dev-cross-plat/performance/script-authoring-considerations?view=powershell-7.5

### Content source URL

https://github.com/MicrosoftDocs/PowerShell-Docs/blob/main/reference/docs-conceptual/dev-cross-plat/performance/script-authoring-considerations.md

### Author

@sdwheeler

### Platform Id

319d7280-c701-6893-7caf-ea95ae00e437

### Document Id

9818d91b-8c5f-337a-f5e1-7a40abd5fd1a

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Prevent unnecessarily collection comparisons #12212

Type of issue

Feedback