This command takes a platform identifier (such as is produced by platform::identify or platform::generic) and returns a list of platform identification tokens that could be checked when searching for code relevant to the platform.
For example, on OSX Leopard you can get this:
% platform::patterns [platform::generic] macosx-ix86 macosx-universal macosx-i386-x86_64 tcl % platform::patterns [platform::identify] macosx10.5-ix86 macosx10.5-universal macosx10.5-i386-x86_64 macosx-ix86 macosx-universal macosx-i386-x86_64 tcl