[Mailman-Developers] [CLI Project] Portioning Commands as Singular or Plural

[Stephen J. Turnbull]

Rajeev S writes:

 > The commands surely do become more intuitive and make more sense,
 > but this has a negative,the number of commands almost doubles.

The number of instances of "class Command" or whatever it's called
doesn't need to double, though.  You could simply have the parser
recognize the relevant plurals as equivalent to the corresponding
singular forms.  If you want to make life hard, you could do that but
in addition in the parse constrain the command to number agreement
(ie, singular forms of the command must take exactly one argument,
while the plural form must take zero, two, or more arguments).

You could really cheat by simply matching the shortest unambiguous
prefix, so that

    show usersallofthemifyouplease

shows all the users, and (probably) just "show u" does too.  I think
this is perhaps the most efficient solution, although it's not obvious
that unsophisticated users would like it as much as us greybeards do.
For bonus points, if the prefix is ambiguous, show the matching
possibilities.  A trie might be a good data structure for this, and
you could build it on the fly from the list of command names (where
ambiguity would of course be a fatal error).

Finally, if you *do* allow abbreviations, you should restrict that
usage to interactive use; scripts should not be allowed to abbreviate
(they'll break if a new command makes the abbreviation ambiguous).