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 rust-lang#378.

Closes rust-lang#18635.

[breaking-change]

Author: pcwalton

src/doc/guide-macros.md

@@ -58,7 +58,7 @@ macro_rules! early_return(
             _ => {}
         }
     );
-)
+);
 // ...
 early_return!(input_1 T::SpecialA);
 // ...
@@ -179,8 +179,8 @@ macro_rules! early_return(
             )+
             _ => {}
         }
-    );
-)
+    )
+);
 // ...
 early_return!(input_1, [T::SpecialA|T::SpecialC|T::SpecialD]);
 // ...
@@ -275,17 +275,17 @@ macro_rules! biased_match (
             _ => { $err }
         };
     )
-)
+);
 
 # enum T1 { Good1(T2, uint), Bad1}
 # struct T2 { body: T3 }
 # enum T3 { Good2(uint), Bad2}
 # fn f(x: T1) -> uint {
 biased_match!((x)       ~ (T1::Good1(g1, val)) else { return 0 };
-              binds g1, val )
+              binds g1, val );
 biased_match!((g1.body) ~ (T3::Good2(result) )
                   else { panic!("Didn't get good_2") };
-              binds result )
+              binds result );
 // complicated stuff goes here
 return result + val;
 # }
@@ -303,7 +303,7 @@ pattern we want is clear:
     ( $( ($e:expr) ~ ($p:pat) else $err:stmt ; )*
       binds $( $bind_res:ident ),*
     )
-# => (0))
+# => (0));
 ~~~~
 
 However, it's not possible to directly expand to nested match statements. But
@@ -323,7 +323,7 @@ input patterns:
 # #![feature(macro_rules)]
 # macro_rules! b(
     ( binds $( $bind_res:ident ),* )
-# => (0))
+# => (0));
 # fn main() {}
 ~~~~
 
@@ -337,7 +337,7 @@ input patterns:
       $( ($e_rest:expr) ~ ($p_rest:pat) else $err_rest:stmt ; )*
       binds  $( $bind_res:ident ),*
     )
-# => (0))
+# => (0));
 ~~~~
 
 The resulting macro looks like this. Note that the separation into
@@ -366,7 +366,7 @@ macro_rules! biased_match_rec (
     );
     // Produce the requested values
     ( binds $( $bind_res:ident ),* ) => ( ($( $bind_res ),*) )
-)
+);
 
 // Wrap the whole thing in a `let`.
 macro_rules! biased_match (
@@ -388,7 +388,7 @@ macro_rules! biased_match (
             binds $( $bind_res ),*
         );
     )
-)
+);
 
 
 # enum T1 { Good1(T2, uint), Bad1}
@@ -398,7 +398,7 @@ macro_rules! biased_match (
 biased_match!(
     (x)       ~ (T1::Good1(g1, val)) else { return 0 };
     (g1.body) ~ (T3::Good2(result) ) else { panic!("Didn't get Good2") };
-    binds val, result )
+    binds val, result );
 // complicated stuff goes here
 return result + val;
 # }
@@ -444,7 +444,7 @@ macro_rules! loop_x (
             $e
         }
     );
-)
+);
 
 fn main() {
     'x: loop {
@@ -482,30 +482,30 @@ An example:
 
 ```rust
 # #![feature(macro_rules)]
-macro_rules! m1 (() => (()))
+macro_rules! m1 (() => (()));
 
 // visible here: m1
 
 mod foo {
     // visible here: m1
 
     #[macro_export]
-    macro_rules! m2 (() => (()))
+    macro_rules! m2 (() => (()));
 
     // visible here: m1, m2
 }
 
 // visible here: m1
 
-macro_rules! m3 (() => (()))
+macro_rules! m3 (() => (()));
 
 // visible here: m1, m3
 
 #[macro_escape]
 mod bar {
     // visible here: m1, m3
 
-    macro_rules! m4 (() => (()))
+    macro_rules! m4 (() => (()));
 
     // visible here: m1, m3, m4
 }

src/etc/regex-match-tests.py

@@ -63,7 +63,7 @@ def read_tests(f):
 def test_tostr(t):
     lineno, pat, text, groups = t
     options = map(group_tostr, groups)
-    return 'mat!(match_%s, r"%s", r"%s", %s)' \
+    return 'mat!{match_%s, r"%s", r"%s", %s}' \
            % (lineno, pat, '' if text == "NULL" else text, ', '.join(options))
 
 

src/libcollections/bit.rs

@@ -2073,7 +2073,7 @@ mod tests {
         let bools = vec![true, false, true, true];
         let bitv: Bitv = bools.iter().map(|n| *n).collect();
 
-        assert_eq!(bitv.iter().collect::<Vec<bool>>(), bools)
+        assert_eq!(bitv.iter().collect::<Vec<bool>>(), bools);
 
         let long = Vec::from_fn(10000, |i| i % 2 == 0);
         let bitv: Bitv = long.iter().map(|n| *n).collect();
@@ -2102,8 +2102,8 @@ mod tests {
         for &b in bools.iter() {
             for &l in lengths.iter() {
                 let bitset = BitvSet::from_bitv(Bitv::with_capacity(l, b));
-                assert_eq!(bitset.contains(&1u), b)
-                assert_eq!(bitset.contains(&(l-1u)), b)
+                assert_eq!(bitset.contains(&1u), b);
+                assert_eq!(bitset.contains(&(l-1u)), b);
                 assert!(!bitset.contains(&l))
             }
         }
@@ -2311,12 +2311,12 @@ mod tests {
         assert!(!a.is_disjoint(&d));
         assert!(!d.is_disjoint(&a));
 
-        assert!(a.is_disjoint(&b))
-        assert!(a.is_disjoint(&c))
-        assert!(b.is_disjoint(&a))
-        assert!(b.is_disjoint(&c))
-        assert!(c.is_disjoint(&a))
-        assert!(c.is_disjoint(&b))
+        assert!(a.is_disjoint(&b));
+        assert!(a.is_disjoint(&c));
+        assert!(b.is_disjoint(&a));
+        assert!(b.is_disjoint(&c));
+        assert!(c.is_disjoint(&a));
+        assert!(c.is_disjoint(&b));
     }
 
     #[test]

src/libcollections/btree/node.rs

@@ -455,7 +455,7 @@ impl<K, V> Node<K, V> {
     /// Take all the values from right, separated by the given key and value
     fn absorb(&mut self, key: K, val: V, right: Node<K, V>) {
         // Just as a sanity check, make sure we can fit this guy in
-        debug_assert!(self.len() + right.len() <= self.capacity())
+        debug_assert!(self.len() + right.len() <= self.capacity());
 
         self.keys.push(key);
         self.vals.push(val);

src/libcollections/enum_set.rs

@@ -373,7 +373,7 @@ mod test {
 
         assert!(e1.is_subset(&e2));
         assert!(e2.is_superset(&e1));
-        assert!(!e3.is_superset(&e2))
+        assert!(!e3.is_superset(&e2));
         assert!(!e2.is_superset(&e3))
     }
 
@@ -400,23 +400,23 @@ mod test {
         let mut e1: EnumSet<Foo> = EnumSet::new();
 
         let elems: Vec<Foo> = e1.iter().collect();
-        assert!(elems.is_empty())
+        assert!(elems.is_empty());
 
         e1.insert(A);
         let elems = e1.iter().collect();
-        assert_eq!(vec![A], elems)
+        assert_eq!(vec![A], elems);
 
         e1.insert(C);
         let elems = e1.iter().collect();
-        assert_eq!(vec![A,C], elems)
+        assert_eq!(vec![A,C], elems);
 
         e1.insert(C);
         let elems = e1.iter().collect();
-        assert_eq!(vec![A,C], elems)
+        assert_eq!(vec![A,C], elems);
 
         e1.insert(B);
         let elems = e1.iter().collect();
-        assert_eq!(vec![A,B,C], elems)
+        assert_eq!(vec![A,B,C], elems);
     }
 
     ///////////////////////////////////////////////////////////////////////////
@@ -434,35 +434,35 @@ mod test {
 
         let e_union = e1 | e2;
         let elems = e_union.iter().collect();
-        assert_eq!(vec![A,B,C], elems)
+        assert_eq!(vec![A,B,C], elems);
 
         let e_intersection = e1 & e2;
         let elems = e_intersection.iter().collect();
-        assert_eq!(vec![C], elems)
+        assert_eq!(vec![C], elems);
 
         // Another way to express intersection
         let e_intersection = e1 - (e1 - e2);
         let elems = e_intersection.iter().collect();
-        assert_eq!(vec![C], elems)
+        assert_eq!(vec![C], elems);
 
         let e_subtract = e1 - e2;
         let elems = e_subtract.iter().collect();
-        assert_eq!(vec![A], elems)
+        assert_eq!(vec![A], elems);
 
         // Bitwise XOR of two sets, aka symmetric difference
         let e_symmetric_diff = e1 ^ e2;
         let elems = e_symmetric_diff.iter().collect();
-        assert_eq!(vec![A,B], elems)
+        assert_eq!(vec![A,B], elems);
 
         // Another way to express symmetric difference
         let e_symmetric_diff = (e1 - e2) | (e2 - e1);
         let elems = e_symmetric_diff.iter().collect();
-        assert_eq!(vec![A,B], elems)
+        assert_eq!(vec![A,B], elems);
 
         // Yet another way to express symmetric difference
         let e_symmetric_diff = (e1 | e2) - (e1 & e2);
         let elems = e_symmetric_diff.iter().collect();
-        assert_eq!(vec![A,B], elems)
+        assert_eq!(vec![A,B], elems);
     }
 
     #[test]

src/libcollections/hash/mod.rs

@@ -113,16 +113,16 @@ macro_rules! impl_hash {
     }
 }
 
-impl_hash!(u8, u8)
-impl_hash!(u16, u16)
-impl_hash!(u32, u32)
-impl_hash!(u64, u64)
-impl_hash!(uint, uint)
-impl_hash!(i8, u8)
-impl_hash!(i16, u16)
-impl_hash!(i32, u32)
-impl_hash!(i64, u64)
-impl_hash!(int, uint)
+impl_hash! { u8, u8 }
+impl_hash! { u16, u16 }
+impl_hash! { u32, u32 }
+impl_hash! { u64, u64 }
+impl_hash! { uint, uint }
+impl_hash! { i8, u8 }
+impl_hash! { i16, u16 }
+impl_hash! { i32, u32 }
+impl_hash! { i64, u64 }
+impl_hash! { int, uint }
 
 impl<S: Writer> Hash<S> for bool {
     #[inline]
@@ -146,7 +146,7 @@ impl<S: Writer> Hash<S> for str {
     }
 }
 
-macro_rules! impl_hash_tuple(
+macro_rules! impl_hash_tuple {
     () => (
         impl<S: Writer> Hash<S> for () {
             #[inline]
@@ -171,21 +171,21 @@ macro_rules! impl_hash_tuple(
             }
         }
     );
-)
-
-impl_hash_tuple!()
-impl_hash_tuple!(A)
-impl_hash_tuple!(A B)
-impl_hash_tuple!(A B C)
-impl_hash_tuple!(A B C D)
-impl_hash_tuple!(A B C D E)
-impl_hash_tuple!(A B C D E F)
-impl_hash_tuple!(A B C D E F G)
-impl_hash_tuple!(A B C D E F G H)
-impl_hash_tuple!(A B C D E F G H I)
-impl_hash_tuple!(A B C D E F G H I J)
-impl_hash_tuple!(A B C D E F G H I J K)
-impl_hash_tuple!(A B C D E F G H I J K L)
+}
+
+impl_hash_tuple! {}
+impl_hash_tuple! { A }
+impl_hash_tuple! { A B }
+impl_hash_tuple! { A B C }
+impl_hash_tuple! { A B C D }
+impl_hash_tuple! { A B C D E }
+impl_hash_tuple! { A B C D E F }
+impl_hash_tuple! { A B C D E F G }
+impl_hash_tuple! { A B C D E F G H }
+impl_hash_tuple! { A B C D E F G H I }
+impl_hash_tuple! { A B C D E F G H I J }
+impl_hash_tuple! { A B C D E F G H I J K }
+impl_hash_tuple! { A B C D E F G H I J K L }
 
 impl<S: Writer, T: Hash<S>> Hash<S> for [T] {
     #[inline]

src/libcollections/hash/sip.rs

@@ -47,7 +47,7 @@ pub struct SipState {
 // because they're needed in the following defs;
 // this design could be improved.
 
-macro_rules! u8to64_le (
+macro_rules! u8to64_le {
     ($buf:expr, $i:expr) =>
     ($buf[0+$i] as u64 |
      $buf[1+$i] as u64 << 8 |
@@ -67,14 +67,14 @@ macro_rules! u8to64_le (
         }
         out
     });
-)
+}
 
-macro_rules! rotl (
+macro_rules! rotl {
     ($x:expr, $b:expr) =>
     (($x << $b) | ($x >> (64 - $b)))
-)
+}
 
-macro_rules! compress (
+macro_rules! compress {
     ($v0:expr, $v1:expr, $v2:expr, $v3:expr) =>
     ({
         $v0 += $v1; $v1 = rotl!($v1, 13); $v1 ^= $v0;
@@ -84,7 +84,7 @@ macro_rules! compress (
         $v2 += $v1; $v1 = rotl!($v1, 17); $v1 ^= $v2;
         $v2 = rotl!($v2, 32);
     })
-)
+}
 
 impl SipState {
     /// Creates a `SipState` that is keyed off the provided keys.