ParseException regarding parameter type declaration.

[phrohdoh]

OS X 10.10.4
Mono 4.0.4 (d481017)
Pash d6c0bdb

Having a $profile of:

$global:shortenPathLength = 3

function prompt {
    $chost = [ConsoleColor]::Green
    $cdelim = [ConsoleColor]::DarkCyan
    $cloc = [ConsoleColor]::Cyan

    Write-Host ' '

    Write-Host ($env:MachineName) -NoNewline -Foregroundcolor $chost
    Write-Host ' {' -NoNewline -Foregroundcolor $cdelim
    Write-Host (Shorten-Path (pwd).Path) -NoNewline -Foregroundcolor $cloc
    Write-Host '} ' -NoNewline -Foregroundcolor $cdelim

    Write-Host "»" -NoNewline -Foregroundcolor $cloc
    ' '

    $Host.UI.RawUI.ForegroundColor = [ConsoleColor]::White
}

function Shorten-Path([String]$path = $pwd) {
   $loc = $path.Replace($HOME, '~')
   # remove prefix for UNC paths
   $loc = $loc -replace '^[^:]+::', ''
   # Make path shorter like tabs in Vim, handle paths starting with \\
   #  and . correctly
   return ($loc -replace "\\(\.?)([^\\]{$shortenPathLength})[^\\]*(?=\\)",'\$1$2')
}

Results in:

Parse error at (20:22): Syntax error, expected: variable, )
> function Shorten-Path([String]$path = $pwd) {
                        ^
  +CategoryInfo: ParserError, Reason: ParseException
  +FullyQualifiedErrorId: Parse

Though this works fine under PS and I see no obvious errors.