> ## Documentation Index
> Fetch the complete documentation index at: https://tally.wharflab.com/llms.txt
> Use this file to discover all available pages before exploring further.

# powershell/PSUseLiteralInitializerForHashtable

> Create hashtables with literal initializers

`powershell/PSUseLiteralInitializerForHashtable` is a PSScriptAnalyzer diagnostic emitted by tally for PowerShell snippets embedded in Dockerfiles.

| Property | Value            |
| -------- | ---------------- |
| Severity | Warning          |
| Category | PSScriptAnalyzer |
| Auto-fix | No               |

## Description

Creating a hashtable using `[hashtable]::new()` or `New-Object -TypeName hashtable` without passing
a `IEqualityComparer` object to the constructor creates a hashtable where the keys are looked-up in
a case-sensitive manner. However, PowerShell is case-insensitive in nature and it is best to create
hashtables with case-insensitive key look-up.

This rule is intended to warn the author of the case-sensitive nature of the hashtable when created
using the `new` method or the `New-Object` cmdlet.

## How to Fix

Create the hashtable using a literal hashtable expression.

## Examples

### Problematic code (`[hashtable]::new()`)

```powershell theme={null}
$hashtable = [hashtable]::new()
```

### Problematic code (`New-Object`)

```powershell theme={null}
$hashtable = New-Object -TypeName hashtable
```

### Correct code

```powershell theme={null}
$hashtable = @{}
```

## Source

This rule documentation is adapted from Microsoft's PSScriptAnalyzer documentation for
[UseLiteralInitializerForHashtable](https://github.com/MicrosoftDocs/PowerShell-Docs-Modules/blob/main/reference/docs-conceptual/PSScriptAnalyzer/Rules/UseLiteralInitializerForHashtable.md),
licensed under [CC BY 4.0](https://creativecommons.org/licenses/by/4.0/).