title: Powershell, File system provider, Get-ChildItem filtering... where are the official docs?
body: <p>As mentioned in <a href="https://stackoverflow.com/questions/4292574/effective-way-to-filter-on-multiple-wildcards-in-poweshell">another question</a>, if you try to do a <code>Get-ChildItem -filter ...</code> command you are more limited than if you used <code>-include</code> instead of <code>-filter</code>.  I'd like to read the official docs for the file system provider's filtering syntax but after a half hour of searching I still haven't found them.  Anyone know where to look?</p>