MonadFail compatibility #21
Description
Trying to build the current package with GHC-8.6, I get:
[13 of 31] Compiling Graphics.PDF.Draw ( Graphics/PDF/Draw.hs, dist/build/Graphics/PDF/Draw.o )
Graphics/PDF/Draw.hs:256:5: error:
• No instance for (Control.Monad.Fail.MonadFail Draw)
arising from a do statement
with the failable pattern ‘(x : xs)’
• In a stmt of a 'do' block: (x : xs) <- gets supplyNames
In the expression:
do (x : xs) <- gets supplyNames
modifyStrict $ \ s -> s {supplyNames = xs}
return x
In an equation for ‘supplyName’:
supplyName
= do (x : xs) <- gets supplyNames
modifyStrict $ \ s -> ...
return x
|
256 | (x:xs) <- gets supplyNames
| ^^^^^^^^^^^^^^^^^^^^^^^^^^
cabal: Failed to build HPDF-1.4.10 (which is required by exe:tttool from
tttool-1.8).
It would be great to have HPDF with current versions of GHC, as tttool heavily relies on it.