diff --git a/src/libfmt_macros/lib.rs b/src/libfmt_macros/lib.rs
index f6dcebf8c50f..30a3bbdc58e9 100644
--- a/src/libfmt_macros/lib.rs
+++ b/src/libfmt_macros/lib.rs
@@ -154,6 +154,7 @@ pub struct Parser<'a> {
     style: Option<usize>,
     /// How many newlines have been seen in the string so far, to adjust the error spans
     seen_newlines: usize,
+    /// Start and end byte offset of every successfuly parsed argument
     pub arg_places: Vec<(usize, usize)>,
 }