Skip to content

Derive TypeFoldable using a proc-macro #66384

New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Merged
merged 5 commits into from
Nov 17, 2019
Merged

Derive TypeFoldable using a proc-macro #66384

Show file tree
Hide file tree
Changes from 1 commit
Commits
Show all changes
5 commits
Select commit Hold shift + click to select a range
9e28e9c
Create TypeFoldable derive proc-macro.
cjgillot Nov 13, 2019
17692b5
Use TypeFoldable derive macro.
cjgillot Nov 13, 2019
d5f5e70
Use TypeFoldable derive macro in librustc_traits.
cjgillot Nov 13, 2019
7214b9a
Retire BraceStructTypeFoldableImpl and TupleStructTypeFoldableImpl.
cjgillot Nov 13, 2019
cb46c35
Use multiple derive clauses.
cjgillot Nov 14, 2019
File filter

Filter by extension

Filter by extension
Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
54 changes: 0 additions & 54 deletions src/librustc/macros.rs
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -324,60 +324,6 @@ macro_rules! EnumLiftImpl {
};
}

#[macro_export]
macro_rules! BraceStructTypeFoldableImpl {
(impl<$($p:tt),*> TypeFoldable<$tcx:tt> for $s:path {
$($field:ident),* $(,)?
} $(where $($wc:tt)*)*) => {
impl<$($p),*> $crate::ty::fold::TypeFoldable<$tcx> for $s
$(where $($wc)*)*
{
fn super_fold_with<V: $crate::ty::fold::TypeFolder<$tcx>>(
&self,
folder: &mut V,
) -> Self {
let $s { $($field,)* } = self;
$s { $($field: $crate::ty::fold::TypeFoldable::fold_with($field, folder),)* }
}

fn super_visit_with<V: $crate::ty::fold::TypeVisitor<$tcx>>(
&self,
visitor: &mut V,
) -> bool {
let $s { $($field,)* } = self;
false $(|| $crate::ty::fold::TypeFoldable::visit_with($field, visitor))*
}
}
};
}

#[macro_export]
macro_rules! TupleStructTypeFoldableImpl {
(impl<$($p:tt),*> TypeFoldable<$tcx:tt> for $s:path {
$($field:ident),* $(,)?
} $(where $($wc:tt)*)*) => {
impl<$($p),*> $crate::ty::fold::TypeFoldable<$tcx> for $s
$(where $($wc)*)*
{
fn super_fold_with<V: $crate::ty::fold::TypeFolder<$tcx>>(
&self,
folder: &mut V,
) -> Self {
let $s($($field,)*)= self;
$s($($crate::ty::fold::TypeFoldable::fold_with($field, folder),)*)
}

fn super_visit_with<V: $crate::ty::fold::TypeVisitor<$tcx>>(
&self,
visitor: &mut V,
) -> bool {
let $s($($field,)*) = self;
false $(|| $crate::ty::fold::TypeFoldable::visit_with($field, visitor))*
}
}
};
}

#[macro_export]
macro_rules! EnumTypeFoldableImpl {
Copy link
Contributor

Choose a reason for hiding this comment

The reason will be displayed to describe this comment to others. Learn more.

Is this still used?

Copy link
Contributor Author

Choose a reason for hiding this comment

The reason will be displayed to describe this comment to others. Learn more.

It is still used to implement TypeFoldable for types defined in librustc's dependencies.

Copy link
Contributor

Choose a reason for hiding this comment

The reason will be displayed to describe this comment to others. Learn more.

Hmm... maybe we should keep the other macros too then since they could also be used for that.

Copy link
Member

Choose a reason for hiding this comment

The reason will be displayed to describe this comment to others. Learn more.

I wonder if we should just use the derives for all librustc* and libsyntax* crates, even if they don't are/depend on librustc.

Copy link
Contributor

Choose a reason for hiding this comment

The reason will be displayed to describe this comment to others. Learn more.

@eddyb As in, add a generic Fold trait for librustc dependencies? That seems maybe too complex. I'm not sure there's many uses of this macro left.

Copy link
Member

Choose a reason for hiding this comment

The reason will be displayed to describe this comment to others. Learn more.

Oh, right, sorry. What I said makes sense for HashStable but not as much this.

(impl<$($p:tt),*> TypeFoldable<$tcx:tt> for $s:path {
Expand Down
3 changes: 1 addition & 2 deletions src/librustc/ty/fold.rs
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -42,8 +42,7 @@ use crate::util::nodemap::FxHashSet;
/// This trait is implemented for every type that can be folded.
/// Basically, every type that has a corresponding method in `TypeFolder`.
///
/// To implement this conveniently, use the
/// `BraceStructTypeFoldableImpl` etc macros found in `macros.rs`.
/// To implement this conveniently, use the derive macro located in librustc_macros.
pub trait TypeFoldable<'tcx>: fmt::Debug + Clone {
fn super_fold_with<F: TypeFolder<'tcx>>(&self, folder: &mut F) -> Self;
fn fold_with<F: TypeFolder<'tcx>>(&self, folder: &mut F) -> Self {
Expand Down