[io grant] Document IO::Spec::Win32.basename

Author: zoffixznet

doc/Type/IO/Spec/Win32.pod6

@@ -16,6 +16,18 @@ need to use C<IO::Spec::*>. Use L«C<IO::Path>|/type/IO::Path» instead..
 
 =head1 Methods
 
+=head2 method basename
+
+    method basename(Str:D $path --> Str:D)
+
+Takes a path as a string and returns a possibly-empty portion after the last
+slash or backslash:
+
+    IO::Spec::Win32.basename("foo/bar/") .perl.say; # OUTPUT: «""␤»
+    IO::Spec::Win32.basename("foo/bar\\").perl.say; # OUTPUT: «""␤»
+    IO::Spec::Win32.basename("foo/bar/.").perl.say; # OUTPUT: «"."␤»
+    IO::Spec::Win32.basename("foo/bar")  .perl.say; # OUTPUT: «"bar"␤»
+
 =head2 method tmpdir
 
 Defined as: