What is GHC.Stack.Types.HasCallStack

[atravers]

[…] not everyone is happy with the current design.

That would seem to be a reasonable summary of this issue:

Use HasCallStack and error in GHC.List and .NonEmpty

• Use HasCallStack and error in GHC.List and .NonEmpty · Issue #5 · haskell/core-libraries-committee · GitHub

It’s also appeared here:

Collectings occurences of incomplete patterns to make them available to Haddock

I feel like this is a relatively “easy” win that we can take from Idris (without having to solve the halting problem). From the Idris documentation: By default, functions in Idris must be covering. That is, there must be patterns which cover all possible values of the inputs types. For example, the following definition will give an error: fromMaybe : Maybe a -> a fromMaybe (Just x) = x This gives an error because fromMaybe Nothing is not defined. Idris reports: frommaybe.idr:1:1--2:1:fromMa…

• Collectings occurences of incomplete patterns to make them available to Haddock - #6 by tomjaguarpaw

• Collectings occurences of incomplete patterns to make them available to Haddock - #7 by Kleidukos

• Collectings occurences of incomplete patterns to make them available to Haddock - #9 by hdgarrood