Re: Autocompletion of commands & arguments

On Nov 15, 2011, at 5:17 AM, Sophie wrote:

> I want to build a Ruby app with the following broad properties
>=20
> - Has some graph of objects, with a root R
> - each object (including R) has some methods, m
> - each m on each object has some args A
> - each A has a set of valid candidates values, defined by method =
candidates_A_m
> - the objects have (string) names
>=20
> I want to build a command-line interface which lets me
>=20
> - start at the root R
> - invoke methods by typing in a prefix and using TAB
> - choose arg values by typing in object-name prefix and TAB
> - getting autocompletion or suggestion-list whenever possible
> - change my "working" location in the graph (like "cd") & continue
>=20
> I have not used Ruby in some time. Am looking for any suggestions on =
useful classes / libraries / methods / apps I should consider to make my =
life easier :-)
>=20
> Thanks!
>=20
>=20
>=20

Hi Sophie,

What would the relation between the objects be ? Named relations ?

You could use an OpenStruct or a hash to hold the related objects and =
then iterate through that list as you press tab.  The hash key would be =
the object name string you indicated in your email.=20

Once on a object if you want to retrieve the public methods you can: =
object.public_methods which returns you an array with the method symbols =
so you can iterate through it.=20

Once on a method you can find out the arity of it with "method.arity"  =
and find out the name of the parameters and if it is requiered with =
"method.parameters"  and call it with "method.call"=20

e.g. =46rom the pick axe:

def m(a, b=3D1, *c, &d)=20
end=20
method(:m).parameters # =3D> [[:req, :a], [:opt, :b], [:rest, :c], =
[:block, :d]]



I would not try to replicate that functionality as luckily Ruby provides =
us with great reflection methods.
 Regards,
V.