test.txt


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fmap f p = Parser ((.) (fmapEither (fmap1st f)) (runParser p));

pure x = Parser (\s -> Right (x, s));
apply pf px = Parser (\s ->
	bindEither (runParser pf s) (\res1 -> case res1 of {
		(f, s') -> bindEither (runParser px s') (\res2 -> case res2 of {
			(x, s'') -> Right (f x, s'')
})}));

fmapEither f e = case e of {
    Left x  -> Left x;
    Right x -> Right (f x)
};

bindEither m f = case m of {
	Left x  -> Left x;
	Right x -> f x
};

fmap1st f p = case p of {
    (l, r) -> (f l, r)
};

runParser p = case p of {
    Parser g -> g
};

(.) f g x = f (g x);
id x = x;

fl1_a = fmap id (Parser g);
fl1_b = Parser g;
fl2_a = fmap ((.) f g) (Parser g);
fl2_b = ((.) (fmap f) (fmap g)) (Parser g);
al1_a = apply (pure id) v;
al1_b = v;