diff --git a/src/protocol/input_source.rs b/src/protocol/input_source.rs
index f2cf10693ae87bc134610829d91344bcc1f221f1..c2c7cd164eea9c9e433e2ecd569b4c65de2ae4ee 100644
--- a/src/protocol/input_source.rs
+++ b/src/protocol/input_source.rs
@@ -170,6 +170,13 @@ impl InputSource {
         return lookup;
     }
 
+    /// Retrieves the column associated with a line. Calling this incurs a read
+    /// lock, so don't spam it in happy-path compiler code.
+    pub(crate) fn get_column(&self, pos: InputPosition) -> u32 {
+        let line_start = self.lookup_line_start_offset(pos.line);
+        return pos.offset - line_start + 1;
+    }
+
     /// Retrieves offset at which line starts (right after newline)
     fn lookup_line_start_offset(&self, line_number: u32) -> u32 {
         let lookup = self.get_lookup();