Rollup merge of rust-lang#43280 - lfairy:token-tree-iter-clone, r=nrc

TimNN · web-flow · commit 7ba4c775ac74 · 2017-07-21T16:33:34.000+02:00
Add #[derive(Clone)] to TokenTreeIter I've found this useful for writing backtracking parsers. The underlying `Cursor` implements `Clone` already, so it's just a matter of adding `#[derive(Clone)]` to the type. r? @jseyfried
diff --git a/src/libproc_macro/lib.rs b/src/libproc_macro/lib.rs
@@ -375,6 +375,7 @@ impl Literal {
 }
 
 /// An iterator over `TokenTree`s.
+#[derive(Clone)]
 #[unstable(feature = "proc_macro", issue = "38356")]
 pub struct TokenTreeIter {
     cursor: tokenstream::Cursor,

Original file line number	Diff line number	Diff line change
`@@ -375,6 +375,7 @@ impl Literal {`
`375`	`375`	`}`
`376`	`376`
`377`	`377`	/// An iterator over `TokenTree`s.
	`378`	`+#[derive(Clone)]`
`378`	`379`	`#[unstable(feature = "proc_macro", issue = "38356")]`
`379`	`380`	`pub struct TokenTreeIter {`
`380`	`381`	`cursor: tokenstream::Cursor,`