Erlang language issues

Thomas Lindgren <>
Thu Apr 18 17:37:58 CEST 2002



From: Richard Carlsson [mailto:]

> You *can* [rewrite guards, etc], even today! (Shameless self-promotion
follows.)

Well, why not do it, then? :-) In the compiler, you can do it after
macro preprocessing too, so the case of strange macros that you mention
subsequently does not occur.

It sounds like a nice tool, btw.

>But this seems to be another of those things that just can't be changed.
>Syntactically, we can and do allow and/or for ,/; - but the semantic
>difference in guards between "top-level" conjunction and
>"expression-level" conjunction will have to remain, I'm afraid. It's a
>fairly subtle thing, and I don't think it will cause any real trouble.

Subtle differences sound somewhat ominous to me; doubly so when there
is no good reason for them (apart from "backwards compatibility").
Indeed, this proliferation was why I raised the question to begin with.
(So we neatly return to the beginning again :-)

-- Thomas




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