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]
That is, only a single expression or item gets parsed, so if there are
any extra tokens (e.g. the start of another item/expression) the user
should be told, rather than silently dropping them.
An example:
macro_rules! foo {
() => {
println("hi");
println("bye);
}
}
would expand to just `println("hi")`, which is almost certainly not
what the programmer wanted.
Fixes#8012.
