filewatcher.ps1

param([string]$folder)
$command="$args"
$filter = "*.*"
$Watcher = New-Object IO.FileSystemWatcher $folder, $filter -Property @{
    IncludeSubdirectories = $true
    EnableRaisingEvents = $true
}

Register-ObjectEvent $Watcher Changed -SourceIdentifier Watcher -Action {
    $command=$event.MessageData
    Write-Host "Running command: $command" -fore green
    $out = Invoke-Expression "$command 2>&1"
    Write-Host "$out"
} -MessageData $command

# Checks for changes in file/folder, executes command when so happens.
# Invoke like this from powershell: PS > .\filewatcher echo hello -folder absolute\path\to
# You need to restart the powershell session to clear the filewatcher
# USE ABSOLUTE PATHS TO FILES AND FOLDERS