Enumerate all functions in a PowerShell script file via AST

Get-Functions.ps1

#Requires -Version 3
# http://d-fens.ch/2015/04/26/nobrainer-enumerate-all-functions-in-a-powershell-script-file-via-ast
[CmdletBinding(
	SupportsShouldProcess = $true
	,
	ConfirmImpact = 'Low'
	,
	DefaultParameterSetName = 'list'
)]
Param
(
	[Parameter(Mandatory = $false, Position = 0, ParameterSetName = 'list')]
	[Switch]
	$ListAvailable = $true
)

BEGIN
{
	function functionInBeginBlock()
	{
		return "functionInBeginBlock";
	}

	function getFunctions($_MyInvocation)
	{
		$OutputParameter = @();
		foreach($BlockName in @("BeginBlock", "ProcessBlock", "EndBlock"))
		{
			$CurrentBlock = $_MyInvocation.MyCommand.ScriptBlock.Ast.$BlockName;
			foreach($Statement in $CurrentBlock.Statements)
			{
				$Extent = $Statement.Extent.ToString();
				if([String]::IsNullOrWhiteSpace($Statement.Name) -Or $Extent -inotmatch ('function\W+(?<name>{0})' -f $Statement.Name))
				{
					continue;
				}
				$OutputParameter += $Statement.Name;
			}
		}
		return $OutputParameter;
	}
}

PROCESS
{
	function functionInProcessBlock()
	{
		return "functionInProcessBlock";
	}
}

END
{
	function functionInEndBlock()
	{
		return "functionInEndBlock";
	}

	function theAnswer()
	{
		return 42;
	}
	
	return getFunctions($MyInvocation);
}

##
 #
 #
 # Copyright 2015 Ronald Rink, d-fens GmbH
 #
 # Licensed under the Apache License, Version 2.0 (the "License");
 # you may not use this file except in compliance with the License.
 # You may obtain a copy of the License at
 #
 # http://www.apache.org/licenses/LICENSE-2.0
 #
 # Unless required by applicable law or agreed to in writing, software
 # distributed under the License is distributed on an "AS IS" BASIS,
 # WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 # See the License for the specific language governing permissions and
 # limitations under the License.
 #
 #