I was interested in the use of ? as a convention for predicates [http://arclanguage.org/item?id=2998]. Seems like Arc still doesn't have a consistent convention for that (and isn't ? still unclaimed territory?). On ! as a convention for setters, I use '= as an almost universal setter, making various specialized setters seem a bit unnecessary. For example, in most cases I'd probably do
(= foo.0 x) ; instead of (scar foo x)
Maybe '=car, '=cdr would be better than 'scar, 'scdr. The s-family just doesn't make much sense anymore since 'assign replaced 'set in its traditional role. Same thing for 'safeset. I'd change it to 'safeassign but it's so long. I thought about 'safe= but '= and 'assign aren't really equivalent (which may actually undermine my argument for '=car).
Yeah, if I rewrote arc from scratch I'd def use the ?/! convention more thoroughly. Your other suggestions seem more subjective, though :) I don't want to go overboard with consistency.
I'm thinking about forking arc, perhaps with an implementation in erlang/lfe (erc?) that would give us threading and pattern-matching and erlang's great scheduler for free.
One of the key core features I find myself wanting is generic functions so annotated types can easily overload primitives like prn and len. If I write an implementation of skip lists or doubly linked lists, for example, it's a royal pain to always remember to (do1 nil ..) at the repl because prn hangs in the presence of circular pointers or pointer explosion.
> Your other suggestions seem more subjective, though :)
I know, I'm afraid I'm earning a reputation here. ;) But out of curiosity, which ones were you thinking of? This point I feel strongly about, though I may have incomplete information:
> The s-family just doesn't make much sense anymore since 'assign replaced 'set in its traditional role.
My understanding is that at some point 'set became the new 'assert and 'assign the new 'set [http://arclanguage.org/item?id=9408]. The #\s in 'scar, 'scdr, 'sref and the "set" in 'safeset are presumably references to 'set, which no longer has anything to do with these functions (and macro). I know it's not a big deal, but isn't it an onion and potential source of confusion?
Yeah that was the one. scar/scdr don't have to make more sense than car/cdr. And they're kinda internal details, same as assign. Most of the time we'll just use (= (car ..) ..). That'll do, no?
I guess so, but changing 'set to 'assign would seem to indicate some sensitivity about the internal details on the language designer's part, and I think they are more important in code-as-spec languages like Arc. Granted you're right the naming of 'scar etc. isn't as important as the naming of commonly used forms like '=.
I believe set was renamed to assign to free up the name for a better use.
The way I think about it: code as spec implies the implementation should be concise and easy to read, and externally exposed names should be approximately hamming encoded. Internal names can be longer without compromising conciseness (which is measured in tokens) or readability.
It's not black and white, just relative priorities.
