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Published
20 hours ago •
mflatt
mflatt
Generated type error for recursive call is not very helpful
I had a typo in a recursive call and stumbled across this a gnarly type error. The a minimal example to reproduce the error is as follows:
#lang plait
(define (f g x)
(f g (x g)))
The original error overflowed my terminal's buffer and I couldn't see the reason for the error. The minimal example tells me that I found a cycle in the type-checker:
typecheck failed: possible cycle in type constraints; increase #:fuel to try more
/home/stites/git/racket/playground/test.rkt:15:9: typecheck failed: possible cycle in type constraints; increase #:fuel to try more
type mismatch: ('a
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'b)))))))))))))))))))))))))))))))))))))))))))))))))))))))))))))))))))))))))))))))))))))))))))))))))))))
->
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'e))))))))))))))))))))))))))))))))))))))))))))))))))))))))))))))))))))))))))))))))))))))))))))))))))))))
->
'f)
sources:
f
location...:
test.rkt:15:9
context...:
/home/stites/.local/share/racket/8.10/pkgs/plait/private/types.rkt:542:0: raise-typecheck-error
/home/stites/.local/share/racket/8.10/pkgs/plait/private/types.rkt:714:27: loop
[repeats 2 more times]
/home/stites/.local/share/racket/8.10/pkgs/plait/private/types.rkt:707:0: let-based-poly!
/home/stites/.local/share/racket/8.10/pkgs/plait/main.rkt:3275:0
/nix/store/ga24q619h10r225n60yp05c59vv6a0nj-racket-8.10/share/racket/collects/syntax/wrap-modbeg.rkt:46:4
