Shell::AutoComplete::Completion::Positional
Maps a completion cursor onto a positional-argument slot.
Class methods
A token that looks like a flag: starts with - but isn't a bare -.
Returns the 0-based positional slot the cursor sits on, accounting for
flags and the values they consume, or nil when the cursor is not on a
positional (it's a flag name, or the value of a value-taking flag).
value_flag_names is the set of flag tokens (canonical, aliases, short
forms) for flags that take a value; bool flags are excluded because they
consume no following token. Mirrors the parser's argument consumption:
--flag=value is a single token, a -- terminator forces everything
after it to be positional.
bare_number_patterns holds the shapes of any bare_number: flags. A
-20 token already reads as a flag, but a +50 does not, and counting
it as a positional would shift every slot after it by one.