Named result variables

[Robert Field]

Thanks Cay  putting this out for discussion, would love to come up with 
some nice solution for this.  I would like to avoid something that 
straddles the snippet and command worlds which are now distinct.

I don't think I expressed my idea very clearly -- mostly because it isn't 
at all clear to me ;-)
What I was thinking was something vaguely tab completion like, in that you 
wind up looking at a well formed snippet not all of which you explicitly 
typed. But not literally a tab nor completion.

Thanks,
Robert



On October 29, 2015 6:50:46 PM Cay Horstmann <cay at horstmann.com> wrote:

> When I teach, I like to use jshell for quick demos. I might predefine
>
> <T> Set<T> setOf(T... values) { return new
> TreeSet<>(Arrays.asList(values)); }
>
> and then construct two sets:
>
> Set<Integer> set1 = setOf(1, 2, 3);
> Set<Integer> set2 = setOf(2, 3, 5);
> set1.removeAll(set2)
>
> Except, that's a lot of typing, so I don't do that. I do
>
> setOf(1, 2, 3);
> setOf(2, 3, 5);
> $1.removeAll($2)
>
> Note the absence of types. The $n are automatically typed.
>
> But I lose track of those $n prettty soon. It would be nice if i could
> name them.
>
> I brought this up at the Java One presentation and suggested
>
> /var set1 $1
>
> or
>
> /var set2
>
> to name the last $n.
>
> Robert thought that was a bit too much like inventing a new langauge
> feature and suggested that one might be able to solve this with tab
> completion instead.
>
> I thought about this a bit and couldn't come up with a compelling way.
> Right now, when one hits Tab on a blank line, one is offered a
> collection of well over 400 possible completions (types, packages,
> classes, $ variables). Using that to get to something like Set<Integer>
> or TreeMap<String, TreeSet<Integer>> isn't satisfactory.
>
> Does anyone else think that an easy way of naming results is worthwhile?
> Any ideas on what the user interface should be?
>
> Cheers,
>
> Cay
>
>
> --
>
> Cay S. Horstmann | http://horstmann.com | mailto:cay at horstmann.com