diff --git a/src/protocol/parser/tokens.rs b/src/protocol/parser/tokens.rs
index 107b6a34e08931bb5319971eb0f1f710b44cb668..ccf6982e268efdeaf5a532c9644a6803fd9d148a 100644
--- a/src/protocol/parser/tokens.rs
+++ b/src/protocol/parser/tokens.rs
@@ -298,6 +298,13 @@ impl<'a> TokenIter<'a> {
         };
     }
 
+    /// Assumes the token is not at the end and returns the starting position
+    /// belonging to the token returned by `next`.
+    pub(crate) fn next_start_position(&self) -> InputPosition {
+        debug_assert!(self.cur < self.end);
+        return self.tokens[self.cur].pos;
+    }
+
     /// Returns the token range belonging to the token returned by `next`. This
     /// assumes that we're not at the end of the range we're iterating over.
     pub(crate) fn next_positions(&self) -> (InputPosition, InputPosition) {