GHCi in colour
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This page documents efforts to colourise GHCi output.
Example
Or a type error:
Output like this would be the result of running, for example:
ghci --colour
and would appear in the console/xterm as ansi terminal coloured output.
Implementation
Using HsColour
An existing tool, HsColour, could be modified to operate interactively. In fact, HsColour is already interactive, and with a small patch added on 2006-12-14 to control ouput buffering better, this works relatively nicely:
ghci 2>&1 | HsColour -tty
HsColour in action
There are small delays however, when lexing certain tokens, and the interaction with readline isn't ideal.
GuiHaskell
Neil Mitchell has a prototype gui haskell wrapper, based on gtk. Does this contain a reasonable ghci wrapper we could steal?
If you have an idea of how to do this nicely, add your proposal here.