List Commands Library for 50g

[DavidM]

I've been thinking about the previously-mentioned "membership" test. Considering what it means for something to be a "member" of something else is a bit more complicated than I originally thought. For example...

It seems fairly straightforward to say:
1 is a member of { 1 2 3 }
and
"a" is a member of { "a" "b" "c" }.

But is "a" a member of "bat"? Or "bat" a member of "battery"?

How about:
is 3 a member of [ 1 2 3 ]? 'x+3-5'?

If I'm to attempt this type of command, there definitely needs to be some clarity of what membership truly means. Otherwise it's probably a good indicator that I've chosen something too general to be useful.

I should probably also mention that looking at the various object types in this context has reminded me of the need to re-emphasize that, in the context of this library's commands, 1 ≠ 1. (or 1,).

Another potential "gotcha" that I've thought about is that, similar to the above, a tagged value won't be treated as equal to its untagged counterpart. This doesn't match the "==" model, and may in fact be an issue for people. As an example, { :myvalue:1 1 } LEQ => 0. Is this a problem?