Clear-Variable.md Documentation Section INPUTS is wrong - allows PSVariable object as input variable in pipe - tested on PS Core 7.5.5

[groeskens]

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Links

• PowerShell-Docs/reference/7.6/Microsoft.PowerShell.Utility/Clear-Variable.md at main · MicrosoftDocs/PowerShell-Docs
• https://github.com/MicrosoftDocs/PowerShell-Docs/blob/6b71dcc6a0e40db15a3cb91153cc0046acb023f8/reference/7.6/Microsoft.PowerShell.Utility/Clear-Variable.md
• "reference/7.6/Microsoft.PowerShell.Utility/Clear-Variable.mdreference/7.6/Microsoft.PowerShell.Utility/Clear-Variable.md"
• PowerShell-Docs/reference/7.6/Microsoft.PowerShell.Utility/Remove-Variable.md at main · MicrosoftDocs/PowerShell-Docs - Cmdlet Remove-Variable

Summary

The section ## INPUTS. in reference/7.6/Microsoft.PowerShell.Utility/Clear-Variable.md is wrong or outdated.
It states:

## INPUTS

### None

You can't pipe objects to this cmdlet.

At least since Powershell Version 7.5.5 it's possible to pipe a variable of type System.Management.Automation.PSVariable to the Cmdlet Clear-Variable. The same is true and documented correctly for the Cmdlet Remove-Variable

Details

Short Test Script

This short test shows, that we can pipe a System.Management.Automation.PSVariable to the Cmdlet Clear-Variable

### Running on Powershell Core Edition 7.5.5 (Windows 11 64-bit x64 AMD64 10.0.26200) 
$PSVersionTable | Select-Object -Property PSVersion, PSEdition | Format-List

# PSVersion : 7.5.5
# PSEdition : Core

# set string variable
$TestDemoStringVariable = "This is a test string"

# clear the variable with pipe works
Get-Variable TestDemoStringVariable | Clear-Variable

# variable is no cleared to $null
$TestDemoStringVariable -eq $null
### Output ### True

# set variable and assign as 

$TestDemoStringVariable = "This is a test string"
$TestDemoStringVariableObject = Get-Variable TestDemoStringVariable
$TestDemoStringVariableObject.GetType().FullName
### Output ### System.Management.Automation.PSVariable

# clear the variable by pipe
$TestDemoStringVariableObject | Clear-Variable
$TestDemoStringVariableObject
### Output ###Name                           Value
### Output ###----                           -----
### Output ###TestDemoStringVariable

# check variable is cleared ($null)
$TestDemoStringVariable -eq $null
### Output ### True

Full Test List

$PSVersionTable.PSVersion.ToString()
### Output ### 7.5.5
$TestDemoStringVariable = "This is a test string"
$TestDemoStringVariable
### Output ### This is a test string
$TestDemoStringVariable.GetType().Name
### Output ### String
(Get-Variable TestDemoStringVariable).GetType().Name
### Output ### PSVariable
Get-Variable TestDemoStringVariable | Clear-Variable
$TestDemoStringVariable
$TestDemoStringVariable.GetType().Name
### Output ### InvalidOperation: You cannot call a method on a null-valued expression.
$TestDemoStringVariable.GetType()
InvalidOperation: You cannot call a method on a null-valued expression.
$TestDemoStringVariable -eq $null
### Output ### True
$TestDemoStringVariable = "This is a test string"
$TestDemoStringVariable
### Output ### This is a test string
$TestDemoStringVariable.GetType().Name
### Output ### String
[PSVariable]"TestDemoStringVariable" | Clear-Variable
$TestDemoStringVariable -eq $null
### Output ### True
$TestDemoStringVariable
[string] $TestDemoStringTypedVariable = "This is a typed string variable"
Get-Variable "TestDemoStringTypedVariable" | Clear-Variable
$TestDemoStringTypedVariable.GetType().Fullname
### Output ### System.String
($TestDemoStringTypedVariable -eq $null)
### Output ### False
$TestDemoStringTypedVariable.Value
($TestDemoStringTypedVariable.Value -eq $null)
### Output ### True
$TestDemoStringVariable = "This is a test string"
$TestDemoStringVariableObject = Get-Variable TestDemoStringVariable
$TestDemoStringVariableObject.GetType().FullName
### Output ### System.Management.Automation.PSVariable
$TestDemoStringVariableObject
### Output ### Name                           Value
### Output ### ----                           -----
### Output ### TestDemoStringVariable         This is a test string

$TestDemoStringVariableObject | Clear-Variable
$TestDemoStringVariableObject
### Output ###Name                           Value
### Output ###----                           -----
### Output ###TestDemoStringVariable

$TestDemoStringVariable -eq $null
### Output ### True

Suggested Fix

Change Section ## INPUTS. in reference/7.6/Microsoft.PowerShell.Utility/Clear-Variable.md as piping a System.Management.Automation.PSVariable object is allowed. The old Information None, "You can't pipe objects to this cmdlet." is wrong.

New suggested text for the section ## INPUTS. starting on line 220 in version 7.6:

## INPUTS

### System.Management.Automation.PSVariable

You can pipe a variable object to this cmdlet.

This is the same text used for the section in reference/7.6/Microsoft.PowerShell.Utility/Remove-Variable.md

[sdwheeler]

@groeskens Thanks for finding this. This part of the docs probably hasn't been touched since PowerShell 2.0. All of the *-Variable command support pipeline input. I will get this fixed.

[sdwheeler]

gcm *-variable -pv cmd | %{ $cmd.Parameters.Name.Attributes[0] | Select @{n='Command'; e={$cmd.Name}}, valuefrompipe*, @{n='Type';e={$cmd.Parameters.Name.ParameterType}} }

Command         ValueFromPipeline ValueFromPipelineByPropertyName Type
-------         ----------------- ------------------------------- ----
Clear-Variable              False                            True System.String[]
Get-Variable                 True                            True System.String[]
New-Variable                False                            True System.String
Remove-Variable             False                            True System.String[]
Set-Variable                False                            True System.String[]