Rollup merge of rust-lang#81241 - m-ou-se:force-expr-macro-rules, r=o…

…li-obk

Turn alloc's force_expr macro into a regular macro_rules.

This turns `alloc`'s `force_expr` macro into a regular `macro_rules`.

Otherwise rust-analyzer doesn't understand `vec![]`. See rust-lang/rust-analyzer#7349 and rust-lang#81080 (comment)

Edit: See rust-lang#81241 (comment) for a discussion of alternatives.

library/alloc/src/lib.rs

@@ -189,11 +189,4 @@ pub mod vec;
 #[unstable(feature = "liballoc_internals", issue = "none", reason = "implementation detail")]
 pub mod __export {
  pub use core::format_args;
-
- /// Force AST node to an expression to improve diagnostics in pattern position.
- #[rustc_macro_transparency = "semitransparent"]
- #[unstable(feature = "liballoc_internals", issue = "none", reason = "implementation detail")]
- pub macro force_expr($e:expr) {
- $e
- }
 }

library/alloc/src/macros.rs

@@ -40,13 +40,13 @@
 #[allow_internal_unstable(box_syntax, liballoc_internals)]
 macro_rules! vec {
  () => (
- $crate::__export::force_expr!($crate::vec::Vec::new())
+ $crate::__rust_force_expr!($crate::vec::Vec::new())
  );
  ($elem:expr; $n:expr) => (
- $crate::__export::force_expr!($crate::vec::from_elem($elem, $n))
+ $crate::__rust_force_expr!($crate::vec::from_elem($elem, $n))
  );
  ($($x:expr),+ $(,)?) => (
- $crate::__export::force_expr!(<[_]>::into_vec(box [$($x),+]))
+ $crate::__rust_force_expr!(<[_]>::into_vec(box [$($x),+]))
  );
 }
 
@@ -111,3 +111,13 @@ macro_rules! format {
  res
  }}
 }
+
+/// Force AST node to an expression to improve diagnostics in pattern position.
+#[doc(hidden)]
+#[macro_export]
+#[unstable(feature = "liballoc_internals", issue = "none", reason = "implementation detail")]
+macro_rules! __rust_force_expr {
+ ($e:expr) => {
+ $e
+ };
+}