about_Functions_Advanced_Parameters is missing some useful attributes

[michaeltlombardi]

Prerequisites

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Links

• https://learn.microsoft.com/powershell/module/microsoft.powershell.core/about/about_functions_advanced_parameters#attributes-of-parameters

Summary

The about_Functions_Advanced_Parameters article includes documentation for several useful attributes you can use on parameters in PowerShell. It either documents them directly or gives an overview and links to further documentation for them.

However, the following useful attributes aren't mentioned:

• PSDefaultValue
• Credential
• Experimental
• PSTypeName
• System.Obsolete

Details

The PSDefaultValue attribute is partially documented in about_Functions at the end of the Named Parameters section and more documented in 12.3.8 The PSDefaultValue attribute of the language specification. Neither is very discoverable.

The Credential attribute is documented in the Credential Attribute Declaration article in the SDK docs. Unfortunately, this isn't very discoverable.

The Experimental attribute is documented in about_Experimental_Features.

The PSTypeName attribute isn't mentioned in the documentation, but it's useful for script and module authors when working with custom objects and decorated types.

The System.Obsolete attribute isn't mentioned in the documentation, but it's useful for script and module authors to mark a parameter as obsolete before removing it.

Suggested Fix

Update about_Functions_Advanced_Parameters to document these attributes and include examples of their usage.