nix repl: Render docs for attributes

src/libutil/position.hh

@@ -7,6 +7,7 @@
 
 #include <cstdint>
 #include <string>
+#include <variant>
 
 #include "source-path.hh"
 
@@ -65,6 +66,13 @@ struct Pos
 
     std::string getSnippetUpTo(const Pos & end) const;
 
+    /**
+     * Get the SourcePath, if the source was loaded from a file.
+     */
+    std::optional<SourcePath> getSourcePath() const {
+        return *std::get_if<SourcePath>(&origin);
+    }
+
     struct LinesIterator {
         using difference_type = size_t;
         using value_type = std::string_view;