List current functions in powershell

You can use the following command to display what functions that are part of your current shell.

Get-ChildItem function:*

To view the code contained in a function - in this example the function "mkdir":

$function:mkdir

If you would like to change a function, simply create a new function of the same name:

function C: {
    Write-Host "You are not allowed on drive C: !"
    Set-Location M:
}

The function TabExpansion is called to generate the list of possible completion matches when using the TAB key.
The function prompt determines what your command prompt looks like (se earlier post) .