Get-AstFunctionName.ps1

function Get-AstFunctionName {
    <#
        .SYNOPSIS
        Retrieves the names of functions from an abstract syntax tree (Ast) in a PowerShell script.

        .DESCRIPTION
        Parses a PowerShell script file or script content to extract function names using an abstract syntax tree (Ast).
        The function supports searching by name, parsing from a file path, or directly from a script string. It can also
        search within nested functions and script block expressions when the -Recurse switch is used.

        .EXAMPLE
        Get-AstFunctionName -Path "C:\Scripts\example.ps1"

        Output:
        ```powershell
        Get-Data
        Set-Configuration
        ```

        Extracts function names from the specified PowerShell script file.

        .EXAMPLE
        Get-AstFunctionName -Script "function Test-Function { param($x) Write-Host $x }"

        Output:
        ```powershell
        Test-Function
        ```

        Extracts function names from the given script string.

        .EXAMPLE
        Get-AstFunctionName -Path "C:\Scripts\example.ps1" -Recurse

        Output:
        ```powershell
        Get-Data
        Set-Configuration
        Helper-Function
        ```

        Extracts function names from the specified script file, including nested functions.

        .OUTPUTS
        System.String

        The names of functions found in the PowerShell script.

        .NOTES
        The name of each function found in the PowerShell script.

        .LINK
        https://psmodule.io/Ast/Functions/Functions/Get-AstFunctionName/
    #>
    [CmdletBinding()]
    param (
        # The name of the command to search for. Defaults to all commands ('*').
        [Parameter()]
        [string] $Name = '*',

        # The path to the PowerShell script file to be parsed.
        # Validate using Test-Path
        [Parameter(
            Mandatory,
            ValueFromPipeline,
            ValueFromPipelineByPropertyName,
            ParameterSetName = 'Path'
        )]
        [ValidateScript({ Test-Path -Path $_ })]
        [string] $Path,

        # The PowerShell script to be parsed.
        [Parameter(
            Mandatory,
            ValueFromPipeline,
            ValueFromPipelineByPropertyName,
            ParameterSetName = 'Script'
        )]
        [string] $Script,

        # Search nested functions and script block expressions.
        [Parameter()]
        [switch] $Recurse
    )

    begin {}

    process {
        switch ($PSCmdlet.ParameterSetName) {
            'Path' {
                $functionAst = Get-AstFunction -Name $Name -Path $Path -Recurse:$Recurse
            }
            'Script' {
                $functionAst = Get-AstFunction -Name $Name -Script $Script -Recurse:$Recurse
            }
        }

        # Process each function and extract the name
        $functionAst.Ast | ForEach-Object {
            $_.Name
        }
    }

    end {}
}