pub fn parse(line: &str) -> Option<Invocation>Expand description
Parse a command line into the command to dispatch and its arguments.
None for an empty line — : then <CR> does nothing, as in vim, rather
than dispatching the empty name and reporting it missing.
A word the grammar knows resolves through VERBS; anything else is
passed through with its ! intact, so what the operator typed is what the
“not found” report names. Silently stripping a bang off an unknown word
would turn :Ghost! into a report about :Ghost, which is a report about
a different thing than the one that failed.