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@@ -2,6 +2,8 @@
 
 ## Typechecking
 
+- 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 
 print the generated type variable for every subexpression in an expression