snake.hs

#!/usr/bin/env runhaskell
import GHC.Clock;import System.IO;q p a b=if p then a else b;i=[(0,0)];w=[0..25]
p s f=putStrLn.("\27[2J\27[1;1H"<>).unlines$["WASD Snake"]<>t<>map(\x->"|"<>map(
 \y->case filter(==(x,y))s of{[]->(q((x,y)==f)'#'' ');[_]->'*';_->'X'})w<>"|")u
 <>t;main=hSetBuffering stdin NoBuffering>>(i,)<$>h i>>=g;t=[replicate 28'-'];c
 s=filter(`notElem`s)$concatMap(\x->map(\y->(x,y))w)u;h s=(c s!!).(`mod`(length(
 c s))).fromEnum.(`div`1000)<$>getMonotonicTimeNSec;m((x,y):_)i=(\(a,b)->(a`mod`
 10,b`mod`26))$case i of{'d'->(x,y+1);'a'->(x,y-1);'w'->(x-1,y);_->(x+1,y);};g(s
 ,f)=p s f>>getChar>>=(\h->pure$m s h:q(m s h==f)s(init s))>>=(\t->(t,)<$>q(head
 t==f)(h t)(pure f))>>=g;u=[0..9]
-- ^10 ------------------------------------------------------------------ 80> --
--
-- Category: base-10-80
-- Tested with: GHC 9.2.6
-- Author: @akshaymankar
--
-- Classic game of snake, control the snake using WASD (up,left,down,right).
-- Limitations:
-- 1. Pressing invalid key would make the snake "fall down".
-- 2. Snake overlapping itself would not immediately end the game, but will show
-- up as 'X'. In fact real snakes can do this all the time!
-- 3. The snake only moves when it is asked to move, i.e. there are no automatic
-- movements making the game much easier