Add some additional topics to todo.md

seanchen1991 · seanchen1991 · commit a448ba59fcdc · 2022-02-21T18:49:07.000-06:00
diff --git a/book/src/todo.md b/book/src/todo.md
@@ -4,3 +4,5 @@ Some topics yet to be written:
 
 - Elaborate on the proof procedure
 - SLG solving – introduce negative reasoning
+- Go over how trait impls are selected and checked
+- Add a section on higher-ranked trait bounds
