robrix

My life's yours, love
That's why you'll find, somebody's on my mind
Wants the world to know
And my hair ain't curled

But youre so mean to me, baby, I know youre gonna drive me away
Some call me honey
Like an old sweet song, 'The Lasting Time'
Some tell me "Billie,

robrix

// cc autotes.m -o autotes -framework Foundation -fobjc-arc && ./autotes
#import <Foundation/Foundation.h>

// use it like lambda(…args…)(…return value…)
#define lambda(...) \
	^(__VA_ARGS__) _lambda_body

#define _lambda_body(...) \
	{ return __VA_ARGS__; }

robrix

((w ord))
((w) (ord))
((word))
((wo rd))
((w o rd))
((w o r d))
((w o r) (d))
((w o) (rd))
((w o) (r d))
((wo) (rd))

robrix

#include <stdio.h>

int main(int argc, char *argv[]) {
	int i = 10;
	while (i \
	          \
	           \
	            \
	             --> 0) { printf("%i\n", i); }
	return EXIT_SUCCESS;

robrix

Interpreting δ as the least fixed point of the nullability equations, ascending from ⊥ = false.

Given S → ϵ ∪ S,

The zeroth iteration is ⊥:

δ⁰(S) = ⊥ = false

The first is computed:

robrix

Interpreting parseNull as the least fixed point of the parse null equations, ascending from ⊥ = {}

Given S → ϵ↓{x} ∪ S,

The zeroth iteration is ⊥:

parseNull⁰(S) = ⊥ = {}

The first is computed:

robrix

a	b	a && b
👎	👎	👎
👍	👎	👎
👎	👍	👎
👍	👍	👍

robrix

a	b	a && b
👎	👎	👎
👍	👎	👎
👎	👍	👎
👍	👍	👍

robrix

newtype Term f = In { out :: f (Term f) }

-- The trivial one
type RCoalgebra1 f a = a -> f (Either (Term f) a)

apo1 :: Functor f => RCoalgebra1 f a -> a -> Term f
apo1 f = In . (fmap fanin) . f
	where fanin = either id (apo1 f)

robrix

data Parser a where
  Cat :: Parser a -> Parser b -> Parser (a, b)
  Alt :: Parser a -> Parser b -> Parser (Either a b)
  Rep :: Parser a -> Parser [a]
  Map :: Parser a -> (a -> b) -> Parser b
  Bnd :: Parser a -> (a -> Parser b) -> Parser b
  Lit :: Char -> Parser Char
  Ret :: [a] -> Parser a
  Nul :: Parser a
  Eps :: Parser a