regex: implement size_hint for set match iterators

Author: srijs

src/re_set.rs

@@ -295,6 +295,10 @@ impl Iterator for SetMatchesIntoIter {
             }
         }
     }
+
+    fn size_hint(&self) -> (usize, Option<usize>) {
+        self.0.size_hint() 
+    }
 }
 
 impl DoubleEndedIterator for SetMatchesIntoIter {
@@ -331,6 +335,10 @@ impl<'a> Iterator for SetMatchesIter<'a> {
             }
         }
     }
+
+    fn size_hint(&self) -> (usize, Option<usize>) {
+        self.0.size_hint() 
+    }
 }
 
 impl<'a> DoubleEndedIterator for SetMatchesIter<'a> {