1 files changed, 27 insertions, 0 deletions
diff --git a/vendor/pest/src/iterators/queueable_token.rs b/vendor/pest/src/iterators/queueable_token.rs
new file mode 100644
index 000000000..7d56749bb
--- /dev/null
+++ b/vendor/pest/src/iterators/queueable_token.rs
@@ -0,0 +1,27 @@
+// pest. The Elegant Parser
+// Copyright (c) 2018 Dragoș Tiselice
+//
+// Licensed under the Apache License, Version 2.0
+// <LICENSE-APACHE or http://www.apache.org/licenses/LICENSE-2.0> or the MIT
+// license <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
+// option. All files in the project carrying such notice may not be copied,
+// modified, or distributed except according to those terms.
+
+// This structure serves to improve performance over Token objects in two ways:
+//
+//   * it is smaller than a Token, leading to both less memory use when stored in the queue but also
+//     increased speed when pushing to the queue
+//   * it finds its pair in O(1) time instead of O(N), since pair positions are known at parse time
+//     and can easily be stored instead of recomputed
+#[derive(Debug)]
+pub enum QueueableToken<R> {
+    Start {
+        end_token_index: usize,
+        input_pos: usize,
+    },
+    End {
+        start_token_index: usize,
+        rule: R,
+        input_pos: usize,
+    },
+}