Unify SyntaxExtension::Decorator and SyntaxExtension::Modifier

[kmcallister]

With a signature like

fn expand(&self, ecx: &mut ExtCtxt, span: Span, meta_item: &MetaItem, orig_item: P<Item>) -> SmallVector<P<Item>>;

to match MacResult::make_items.

[Manishearth]

Please, this.

For #[jstraceable] in Servo, I've accomplished this by writing an ItemDecorator which expands into more attributes.

(Though in the long run that's probably what we want since it's more easily extended)

[Manishearth]

(I'll probably work on this if I get time next week -- if someone else is interested feel free to take it)

[druzn3k]

As I am waiting for a response in #9303, i would like to work on this in the meantime. @Manishearth, it's ok with you or are you still working on the issue?

[Manishearth]

@druzn3k Sure, work on it if you want. I had a partial patch but at the moment my rustc build is being used for a different feature so I won't be working on it anyway.

[druzn3k]

would you mind sharing the patch with me @Manishearth? :)

[Manishearth]

I don't think I have it anymore, I did a clean clone the other day :p Anyway, it's rather simple IIRC.

[druzn3k]

Thank you anyway @Manishearth :)

[kmcallister]

We now have Decorator, Modifier, and MultiModifier. Can we remove the first two?

[steveklabnik]

Grepping around, I think this is fixed. I vaguely remember @nrc sending a PR to unify this stuff as well. Can anyone else confirm?

[nrc]

This is still an issue, we're basically waiting on the procedural macros changes to fix this (currently in RFC).

[steveklabnik]

procedural macros are stable; closing!

[petrochenkov]

Procedural macros 1.2 are stabilized, but this cleanup of legacy plugins is still not done.
I don't think it makes sense to track it with an issue though.

[steveklabnik]

Yes, that's a good point. thanks