Support declarative macros 2.0

[edwin0cheng]

Some source code in rustc start to using decl-macro :

https://github.com/rust-lang/rust/blob/82cf3a4486bc882207a09bf0d9e2dea4632781aa/src/libsyntax_ext/lib.rs#L52-L60

It would be nice to support it (at least in parser) or ignore it right now to have a better experince on browsing rustc source code by RA.

[DJMcNab]

We also need this for e.g. https://doc.rust-lang.org/std/clone/macro.Clone.html to get proper doc comments for derive macros.

[edwin0cheng]

In ra_parser, should we add a new ast::MacroCall2 or reuse ast::MacroCall and let hir decided which one to be ?

[DJMcNab]

I don't think we should reuse macro call

[matklad]

For macro keyword, calls and defs have different syntax, so we should just add a dedicated node for this, MacroDef

[DJMcNab]

Hold on though - in #2315 I'm already using MacroDef to mean macro_rules or procedural macros. We either need a different name for that or a different name for this

[matklad]

I don't think ra_syntax should now anything about proc_macros: proc_macros don't have a syntax-level representation

…

On Wed, 20 Nov 2019 at 10:51, Daniel McNab ***@***.***> wrote: Hold on though - in #2315 <#2315> I'm already using MacroDef to mean macro_rules or procedural macros. We either need a different name for that or a different name for this — You are receiving this because you commented. Reply to this email directly, view it on GitHub <#2248>, or unsubscribe <https://github.com/notifications/unsubscribe-auth/AANB3M4CDMIQSDZJE3TKKHDQUTT67ANCNFSM4JNVCFUA> .

[DJMcNab]

I needed to do that because a lot of stuff used e.g. the NameOwner impl of MacroDefId.ast_id, and MacroDef needed to implement from and To source, which needed a Syntax node implementor to cast it from and to

[jonas-schievink]

FYI: Rust 1.51.0 will stabilize core::ptr::{addr_of, addr_of_mut}, which are "2.0" macros

[edwin0cheng]

Since #8212 was merged. Let's close it first and handle related problems (Macro hygiene in macro 2.0) in separate issues.