librustc: Always parse `macro!()`/`macro![]` as expressions if not

followed by a semicolon.

This allows code like `vec![1i, 2, 3].len();` to work.

This breaks code that uses macros as statements without putting
semicolons after them, such as:

    fn main() {
        ...
        assert!(a == b)
        assert!(c == d)
        println(...);
    }

It also breaks code that uses macros as items without semicolons:

    local_data_key!(foo)

    fn main() {
        println("hello world")
    }

Add semicolons to fix this code. Those two examples can be fixed as
follows:

    fn main() {
        ...
        assert!(a == b);
        assert!(c == d);
        println(...);
    }

    local_data_key!(foo);

    fn main() {
        println("hello world")
    }

RFC #378.

Closes #18635.

[breaking-change]

1 files changed, 2 insertions, 2 deletions

diff --git a/src/libstd/num/int_macros.rs b/src/libstd/num/int_macros.rs
index 2f1162d28e5..fce150c4ad1 100644
--- a/src/libstd/num/int_macros.rs
+++ b/src/libstd/num/int_macros.rs
@@ -12,6 +12,6 @@
 #![macro_escape]
 #![doc(hidden)]
 
-macro_rules! int_module (($T:ty) => (
+macro_rules! int_module { ($T:ty) => (
 
-))
+) }