This package provides an easy way to insert GHC language pragmas.
The list of currently supported extensions is taken from GHC 8.8.4 .
The package can be loaded like this, using https:/jwiegley/use-package.
(use-package ghc-extensions
:load-path "path/to/package"
:bind (("C-c C-g" . ghc-extensions-insert-at-point))
)