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@@ -1,7 +1,12 @@
 # TODO items
 
+## Reduction
+ - make a good type for actual language builtins to avoid string comparisons
+
 ## Typechecking
 
+- make a type to represent types rather than relying on string comparisons
+
 - look at https://rickyhan.com/jekyll/update/2018/05/26/hindley-milner-tutorial-rust.html
 
 - cf. the notation mentioned in the cardelli paper, the debug information for the `typechecking` pass should