user said "inline"!
To avoid this we pre-emptively eta-expand the definition, so that foo
-has arity 2 (one for the Eq and one for x); and that in turn should
-mean that (foo d) is a PAP and we don't share it.
-
+has the arity with which it is declared in the source code. In this
+example it has arity 2 (one for the Eq and one for x). Doing this
+should mean that (foo d) is a PAP and we don't share it.
Note [Nested arities]
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