Config for GHCi with pretty output

ghci.conf

-- To run: 
--    cabal repl -b pretty-simple
--
-- Colorizing and pretty-printing ghci output
-- requires: pretty-simple
:set -interactive-print=Text.Pretty.Simple.pPrint

-- green bold lambdas and multiline mode
:set prompt      "\ESC[1;32mλ: \ESC[m"
:set prompt-cont "\ESC[1;32mλ| \ESC[m"

-- useful flags
:set -fprint-explicit-foralls
:set +m

-- useful extensions by default
:set -XTypeApplications -XKindSignatures

-- useful default imports
import Data.Kind (Type, Constraint)

-- helpful macros
:def package \ m -> return $ ":! ghc-pkg --simple-output find-module " ++ m
:def no-pretty \_ -> return (":set -interactive-print=System.IO.print")
:def rr \_ -> return ":script ~/.ghc/ghci.conf"

I found the problem. The :load will drop pre define things something like ghciColor.
pretty-simple sounds like a good solution.

Here's my modification. It also works for stack, whatever you're under a stack project or not.

Thanks @chshersh

:def pretty \_ -> return (":set -interactive-print=Text.Pretty.Simple.pPrint")
:def no-pretty \_ -> return (":set -interactive-print System.IO.print")

:def package \m -> return $ ":! ghc-pkg --simple-output find-module " ++ m
:def rr \_ -> return ":script ~/.ghci"

:set prompt  "\ESC[1;32mλ \ESC[m"

:set +m
:set +s
:set +t

:set -package pretty-simple

:set -fprint-explicit-foralls
:set -interactive-print=Text.Pretty.Simple.pPrint
:set -XTypeApplications -XKindSignatures

import Data.Kind (Type, Constraint)