commit fe1104628661ad09dcbdf9694d10c25a8f7ad63a
author Alex Crichton <alex@alexcrichton.com> Thu Jun 01 12:49:27 2017 -0700
committer Alex Crichton <alex@alexcrichton.com> Mon Jul 10 09:47:28 2017 -0700
tree 743a14b1ae52cf2433cb5ef8e5fdf2e7f781cb97
parent 0aa50e0cc993ed7f86b7132e0bfe4dae7a2a3ed1

Support for `yield`

src/expr.rs

diff --git a/src/expr.rs b/src/expr.rs
index 6783b7d..db3fb55 100644
--- a/src/expr.rs
+++ b/src/expr.rs
@@ -346,6 +346,14 @@
             pub catch_token: tokens::Catch,
             pub block: Block,
         }),
+
+        /// A yield expression.
+        ///
+        /// E.g. `yield expr`
+        pub Yield(ExprYield #full {
+            pub yield_token: tokens::Yield,
+            pub expr: Option<Box<Expr>>,
+        }),
     }
 }
 
@@ -1164,6 +1172,8 @@
         |
         syn!(ExprCatch) => { ExprKind::Catch }
         |
+        syn!(ExprYield) => { ExprKind::Yield }
+        |
         call!(expr_closure, allow_struct)
         |
         cond_reduce!(allow_block, map!(syn!(ExprBlock), ExprKind::Block))
@@ -1208,6 +1218,8 @@
         |
         syn!(ExprCatch) => { ExprKind::Catch }
         |
+        syn!(ExprYield) => { ExprKind::Yield }
+        |
         syn!(ExprBlock) => { ExprKind::Block }
     ), Expr::from));
 
@@ -1473,6 +1485,18 @@
     }
 
     #[cfg(feature = "full")]
+    impl Synom for ExprYield {
+        named!(parse -> Self, do_parse!(
+            yield_: syn!(Yield) >>
+            expr: option!(syn!(Expr)) >>
+            (ExprYield {
+                yield_token: yield_,
+                expr: expr.map(Box::new),
+            })
+        ));
+    }
+
+    #[cfg(feature = "full")]
     fn arm_requires_comma(arm: &Arm) -> bool {
         if let ExprKind::Block(ExprBlock { unsafety: Unsafety::Normal, .. }) = arm.body.node {
             false
@@ -2449,6 +2473,14 @@
     }
 
     #[cfg(feature = "full")]
+    impl ToTokens for ExprYield {
+        fn to_tokens(&self, tokens: &mut Tokens) {
+            self.yield_token.to_tokens(tokens);
+            self.expr.to_tokens(tokens);
+        }
+    }
+
+    #[cfg(feature = "full")]
     impl ToTokens for ExprClosure {
         fn to_tokens(&self, tokens: &mut Tokens) {
             self.capture.to_tokens(tokens);

src/fold.rs

diff --git a/src/fold.rs b/src/fold.rs
index 99b66cb..5794f52 100644
--- a/src/fold.rs
+++ b/src/fold.rs
@@ -892,6 +892,13 @@
                 })
             }
             #[cfg(feature = "full")]
+            Yield(e) => {
+                Yield(ExprYield {
+                    expr: e.expr.map(|e| e.lift(|e| folder.fold_expr(e))),
+                    ..e
+                })
+            }
+            #[cfg(feature = "full")]
             Closure(e) => {
                 Closure(ExprClosure {
                     decl: e.decl.lift(|v| folder.fold_fn_decl(v)),

src/visit.rs

diff --git a/src/visit.rs b/src/visit.rs
index 550afb7..f14fbdc 100644
--- a/src/visit.rs
+++ b/src/visit.rs
@@ -591,6 +591,12 @@
             visitor.visit_expr(amt);
         }
         #[cfg(feature = "full")]
+        Yield(ExprYield { ref expr, .. }) => {
+            if let Some(ref expr) = *expr {
+                visitor.visit_expr(expr);
+            }
+        }
+        #[cfg(feature = "full")]
         TupField(ExprTupField { ref expr, .. }) |
         Unary(ExprUnary { ref expr, .. }) |
         Box(ExprBox { ref expr, .. }) |