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Opened by Jakob Brünker@JakobBruenker

ghci's :type still ignores ill-kinded type application with -fdefer-type-errors

Summary

#16376 (closed) was fixed in 8.10, but the same problem is still there if -fdefer-type-errors is enabled.

Steps to reproduce

Write :set -fdefer-type-errors followed by :t id @Maybe in ghci. It produces no ouput, neither an error nor anything else.

Expected output

<interactive>:1:5: warning: [-Wdeferred-type-errors]:
    • Expecting one more argument to ‘Maybe’
      Expected a type, but ‘Maybe’ has kind ‘* -> *’
    • In the type ‘Maybe’
      In the expression: id @Maybe
id @Maybe :: t

Environment

  • GHC version used: 9.1.20201223

Optional:

  • Operating System: Ubuntu inside WSL2 inside Windows 10
  • System Architecture: x86_64