type variable binders should draw arrows in DrRacket

[pnwamk]

(: id (All (X) (-> X X)))
(define id values)

Mousing over the X's in (-> X X) should draw an arrow back to the X in (X) in DrRacket. Apparently this used to work but has not for a while =(

[rfindler]

Check Syntax has a programmatic interface that exposes the information that it computes from the fully expanded version of a program (it then interprets that information to draw arrows). This interface was exposed mostly for unit tests for problems like this one. It is pretty low-level, but redex/tests/check-syntax-test has some examples that, combined with the docs, should make it possible to avoid sentences like "Apparently this used to work but has not for a while" :).

[pnwamk]

Thanks, @rfindler! =)

[rfindler]

Let me know if you run into trouble!