Allow macrocall as function sig #55040
Conversation
|
I think this makes sense. A macro call is a very similar form to a call so it fits smoothly, and you might as well be able to generate a function signature with a macro. |
src/julia-parser.scm
Outdated
| decl-sig))) | ||
| (let ((ex (parse-unary-prefix s))) | ||
| (if (and (pair? ex) (eq? (car ex) 'macrocall)) | ||
| ex |
There was a problem hiding this comment.
This is the only tricky bit --- do we allow function @mac(x, y)::T (or with where) or does the macro generate the entire signature? Probably the latter (as you have it) but it made me stop and think.
There was a problem hiding this comment.
We already have that @mac(x, y)::T is allowed in call position and the ::T is not passed to the macro (unfortunately)
I guess we can allow you to return more syntax than the macro receives, but it seems a bit odd since it means you can end up generating redundant and/or conflicting type assertions.
There was a problem hiding this comment.
I don't think a redundant expansion, you can always do the same directly without going through the parser. Needs to be some kind of lowering error or be given semantics. But that's independent of whether it's a legal parse or not.
There was a problem hiding this comment.
I just mean that the macro can't handle the case that it wants to insert a type assertion when one is already present - the obvious way to do that would have been to pass that syntax to the macro but I don't think we can do that
Unless I'm missing something?
@KristofferC requested that `function @main(args) end` should work. This is currently a parse error. This PR makes it work as expected by allowing macrocall as a valid signature in function (needs to exapand to a call expr). Note that this is only the flisp changes. If this PR is accepted, an equivalent change would need to be made in JuliaSyntax.
|
Seems like people like the change, so I've addressed @JeffBezanson 's review comment and put up the same change in JuliaSyntax.jl |
Keno
changed the title
@KristofferC requested that
function @main(args) endshould work. This is currently a parse error. This PR makes it work as expected by allowing macrocall as a valid signature in function (needs to exapand to a call expr). Note that this is only the flisp changes. If this PR is accepted, an equivalent change would need to be made in JuliaSyntax.