Skip to content
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.

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

Shorten name to trait_variant::make #8

Merged
merged 2 commits into from
Dec 18, 2023
Merged
Show file tree
Hide file tree
Changes from all commits
Commits
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
8 changes: 4 additions & 4 deletions README.md
Original file line number Diff line number Diff line change
Expand Up @@ -2,12 +2,12 @@

Utilities for working with impl traits in Rust.

## `make_variant`
## `trait_variant`

`make_variant` generates a specialized version of a base trait that uses `async fn` and/or `-> impl Trait`. For example, if you want a `Send`able version of your trait, you'd write:
`trait_variant` generates a specialized version of a base trait that uses `async fn` and/or `-> impl Trait`. For example, if you want a `Send`able version of your trait, you'd write:

```rust
#[trait_variant::make_variant(SendIntFactory: Send)]
#[trait_variant::make(SendIntFactory: Send)]
trait IntFactory {
async fn make(&self) -> i32;
// ..or..
Expand All @@ -22,7 +22,7 @@ Implementers of the trait can choose to implement the variant instead of the ori

## `trait_transformer`

`trait_transformer` does the same thing as `make_variant`, but using experimental nightly-only syntax that depends on the `return_type_notation` feature. It may be used to experiment with new kinds of trait transformations in the future.
`trait_transformer` does the same thing as `make`, but using experimental nightly-only syntax that depends on the `return_type_notation` feature. It may be used to experiment with new kinds of trait transformations in the future.

#### License and usage notes

Expand Down
13 changes: 9 additions & 4 deletions trait-variant/examples/variant.rs
Original file line number Diff line number Diff line change
Expand Up @@ -8,10 +8,8 @@

use std::future::Future;

use trait_variant::make_variant;

#[make_variant(SendIntFactory: Send)]
trait IntFactory {
#[trait_variant::make(IntFactory: Send)]
pub trait LocalIntFactory {
const NAME: &'static str;

type MyFut<'a>: Future
Expand All @@ -24,4 +22,11 @@ trait IntFactory {
fn another_async(&self, input: Result<(), &str>) -> Self::MyFut<'_>;
}

#[allow(dead_code)]
fn spawn_task(factory: impl IntFactory + 'static) {
tokio::spawn(async move {
let _int = factory.make(1, "foo").await;
});
}

fn main() {}
4 changes: 2 additions & 2 deletions trait-variant/src/lib.rs
Original file line number Diff line number Diff line change
Expand Up @@ -20,9 +20,9 @@ pub fn trait_transformer(
}

#[proc_macro_attribute]
pub fn make_variant(
pub fn make(
attr: proc_macro::TokenStream,
item: proc_macro::TokenStream,
) -> proc_macro::TokenStream {
variant::make_variant(attr, item)
variant::make(attr, item)
}
24 changes: 19 additions & 5 deletions trait-variant/src/variant.rs
Original file line number Diff line number Diff line change
Expand Up @@ -49,22 +49,36 @@ impl Parse for MakeVariant {
}
}

pub fn make_variant(
pub fn make(
attr: proc_macro::TokenStream,
item: proc_macro::TokenStream,
) -> proc_macro::TokenStream {
let attrs = parse_macro_input!(attr as Attrs);
let item = parse_macro_input!(item as ItemTrait);

let maybe_allow_async_lint = if attrs
.variant
.bounds
.iter()
.any(|b| b.path.segments.last().unwrap().ident.to_string() == "Send")
{
quote! { #[allow(async_fn_in_trait)] }
} else {
quote! {}
};

let variant = mk_variant(&attrs, &item);
let blanket_impl = mk_blanket_impl(&attrs, &item);
let output = quote! {

quote! {
#maybe_allow_async_lint
#item

#variant
#blanket_impl
};

output.into()
#blanket_impl
}
.into()
}

fn mk_variant(attrs: &Attrs, tr: &ItemTrait) -> TokenStream {
Expand Down