Allow trailing commas

src/lib.rs

@@ -15,10 +15,10 @@ macro_rules! system {
 
 #[macro_export]
 macro_rules! args_to_systemdata {
-    ( ( $name:ident : $ty:ty ) ) => {
+    ( ( $name:ident : $ty:ty $(,)? ) ) => {
         ( specs::ReadStorage<'a, $ty> ,)
     };
-    ( ( mut $name:ident : $ty:ty ) ) => {
+    ( ( mut $name:ident : $ty:ty $(,)? ) ) => {
         ( specs::WriteStorage<'a, $ty> ,)
     };
     ( ( $name:ident : $ty:ty , $($tok:tt)* ) ) => {
@@ -31,10 +31,10 @@ macro_rules! args_to_systemdata {
 
 #[macro_export]
 macro_rules! args_to_pat {
-    ( ( $name:ident : $ty:ty ) ) => {
+    ( ( $name:ident : $ty:ty $(,)? ) ) => {
         ( $name ,)
     };
-    ( ( mut $name:ident : $ty:ty ) ) => {
+    ( ( mut $name:ident : $ty:ty $(,)? ) ) => {
         ( mut $name ,)
     };
     ( ( $name:ident : $ty:ty , $($tok:tt)* ) ) => {
@@ -47,10 +47,10 @@ macro_rules! args_to_pat {
 
 #[macro_export]
 macro_rules! args_to_join {
-    ( ( $name:ident : $ty:ty ) ) => {
+    ( ( $name:ident : $ty:ty $(,)? ) ) => {
         ( & $name ,)
     };
-    ( ( mut $name:ident : $ty:ty ) ) => {
+    ( ( mut $name:ident : $ty:ty $(,)? ) ) => {
         ( &mut $name ,)
     };
     ( ( $name:ident : $ty:ty , $($tok:tt)* ) ) => {
@@ -77,7 +77,7 @@ mod tests {
         type Storage = specs::VecStorage<Mov>;
     }
 
-    system!{ Foo (_x: Mov, mut y: Pos) =>
+    system!{ Foo (_x: Mov, mut y: Pos,) =>
         y.x += 1;
     }
 }