Added expand_register option.

autoload/highlight.vim

@@ -30,6 +30,21 @@ let s:active_register = "\""
 let s:registry = {}
 
 
+" FUNCTION: ExpandRegister(reg) {{{1
+" ==============================================================================
+" Convenience method to determine which register is being currently used.
+" The unnamed register defaults to the last used register to avoid having to
+" constantly prefix registration. This can be changed by setting the value of
+" g:persist_unnamed_register to 1.
+
+function! highlight#expand_register(reg)
+  if !g:persist_unnamed_register && a:reg ==# '"'
+    return s:active_register
+  endif
+  return a:reg
+endfunction
+
+
 " FUNCTION: ExpandFlag(flag) {{{1
 " ==============================================================================
 " Convenience method used to make the mappings in plugin/highlight.vim a bit