Marios Control Program

A sort of uGHCi with bells and whistles preconfigured to work as a shell.

Features

• Background jobs (forkIO) have access to the externalPrint function from haskeline, allowing output to the console without disturbing the prompt.
• Host executables all available qualified in the OS module.
• Simple support for changing the current directory without trashing the context.
• Simple expression completion (nothing GHCi can't also do).
• Integrated internet radio player with current title reporting via externalPrint.
• Direct rendering of diagrams to console via diagrams-braille.

All this project does is bring together some very nice Haskell libraries. There is really no novelty here. All the hard work has been done by the maintainers/authors of the packages this project depends on.

Dependencies

MCP uses GStreamer to play background music.

# apt install libgirepository1.0-dev libgstreamer1.0-dev

Running

Currently, the best way to build/run this program is via stack:

$ stack run

Examples

Changing directories

% getCurrentDirectory
"/home/mlang/src/mcp"
% cd
% getCurrentDirectory
"/home/mlang"
% cd "src/mcp"
% getCurrentDirectory
"/home/mlang/src/mcp"

Globbing

% glob "lib/*.hs"
["lib/Ops.hs","lib/Radio.hs","lib/OS.hs"]
% OS.ls =<< glob "lib/*.hs"
lib/Ops.hs  lib/OS.hs  lib/Radio.hs

Threads and Variables

% let watch r p = forkIO . forever $ printProc p >> readIORef r >>= OS.sleep
% delay <- newIORef 10
% clock <- watch delay OS.date
Sat Mar  2 21:32:28 CET 2019
Sat Mar  2 21:32:38 CET 2019
% writeIORef delay 5
Sat Mar  2 21:32:48 CET 2019
Sat Mar  2 21:32:53 CET 2019
Sat Mar  2 21:32:58 CET 2019
Sat Mar  2 21:33:03 CET 2019
% killThread clock

Drawing diagrams

% draw $ circle 1 <> square (sqrt 2)
⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⣀⡤⠴⠒⠛⠉⠉⠉⠉⠉⠉⠉⠉⠛⠒⠦⢤⣀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀
⠀⠀⠀⠀⠀⠀⠀⠀⣠⠖⠋⠁⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠈⠙⠲⣄⠀⠀⠀⠀⠀⠀⠀⠀
⠀⠀⠀⠀⠀⢀⣴⣋⣀⣀⣀⣀⣀⣀⣀⣀⣀⣀⣀⣀⣀⣀⣀⣀⣀⣀⣀⣀⣀⣀⣀⣀⣙⣦⡀⠀⠀⠀⠀⠀
⠀⠀⠀⠀⡴⢻⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⡟⢦⠀⠀⠀⠀
⠀⠀⢠⠞⠀⢸⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⡇⠀⠳⡄⠀⠀
⠀⢠⠏⠀⠀⢸⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⡇⠀⠀⠹⡄⠀
⢀⡏⠀⠀⠀⢸⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⡇⠀⠀⠀⢹⡀
⣼⠀⠀⠀⠀⢸⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⡇⠀⠀⠀⠀⣧
⡇⠀⠀⠀⠀⢸⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⡇⠀⠀⠀⠀⢸
⡇⠀⠀⠀⠀⢸⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⡇⠀⠀⠀⠀⢸
⡇⠀⠀⠀⠀⢸⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⡇⠀⠀⠀⠀⢸
⡇⠀⠀⠀⠀⢸⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⡇⠀⠀⠀⠀⢸
⢻⠀⠀⠀⠀⢸⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⡇⠀⠀⠀⠀⡟
⠈⣇⠀⠀⠀⢸⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⡇⠀⠀⠀⣸⠁
⠀⠘⣆⠀⠀⢸⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⡇⠀⠀⣰⠃⠀
⠀⠀⠘⢦⠀⢸⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⡇⠀⡴⠃⠀⠀
⠀⠀⠀⠀⠳⣼⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⣧⠞⠀⠀⠀⠀
⠀⠀⠀⠀⠀⠈⠻⣍⠉⠉⠉⠉⠉⠉⠉⠉⠉⠉⠉⠉⠉⠉⠉⠉⠉⠉⠉⠉⠉⠉⠉⠉⣩⠟⠁⠀⠀⠀⠀⠀
⠀⠀⠀⠀⠀⠀⠀⠀⠙⠦⣄⡀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⢀⣠⠴⠋⠀⠀⠀⠀⠀⠀⠀⠀
⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠉⠓⠲⠤⣤⣀⣀⣀⣀⣀⣀⣀⣀⣤⠤⠖⠚⠉⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀