Add DefaultSignatures #2
Open
Conversation
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
It's actually possible to use `DefaultSignatures`, in a slightly different way than you did. You need to use heterogeneous equality (`(~~)`) rather than homogeneous (`(~)`), and (as will generally be the case) you need to make the default signature the same as the actual signature except for constraints. Unfortunately, GHC 8.0.2 panics with the code I've written; it compiles in a recent 8.2.
Sign up for free
to join this conversation on GitHub.
Already have an account?
Sign in to comment
Add this suggestion to a batch that can be applied as a single commit.
This suggestion is invalid because no changes were made to the code.
Suggestions cannot be applied while the pull request is closed.
Suggestions cannot be applied while viewing a subset of changes.
Only one suggestion per line can be applied in a batch.
Add this suggestion to a batch that can be applied as a single commit.
Applying suggestions on deleted lines is not supported.
You must change the existing code in this line in order to create a valid suggestion.
Outdated suggestions cannot be applied.
This suggestion has been applied or marked resolved.
Suggestions cannot be applied from pending reviews.
Suggestions cannot be applied on multi-line comments.
Suggestions cannot be applied while the pull request is queued to merge.
Suggestion cannot be applied right now. Please check back later.
It's actually possible to use
DefaultSignatures, in a slightlydifferent way than you did. You need to use heterogeneous equality
(
(~~)) rather than homogeneous ((~)), and (as will generallybe the case) you need to make the default signature the same as
the actual signature except for constraints. Unfortunately, GHC
8.0.2 panics with the code I've written; it compiles in a recent
8.2.
Note: you may wish to use CPP to enable this to compile with 8.0.2