wildmenu - command-line completion

When ‘wildmenu’ is on, command-line completion operates in an enhanced mode. On pressing ‘wildchar’ (usually ) to invoke completion, the possible matches are shown. When ‘wildoptions’ contains “pum”, then the completion matches are shown in a popup menu. Otherwise they are displayed just above the command line, with the first match highlighted (overwriting the status line, if there is one).