initial WIP

README.md

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+# nothing
+
+A WIP implementation of Tom Stuart’s [Programming with Nothing](https://www.youtube.com/watch?v=VUhlNx_-wYk)
+challenge in ES6. I got to factorial, and will try to do the whole thing soon.

nothing-helper.js

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+module.exports = {
+  to_int: (f) => f(n => n+1)(0),
+  to_boolean: (f) => f(true)(false),
+};

nothing.js

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+const ZERO = f => x => x;
+const ONE = f => x => f(x);
+const TWO = f => x => f(f(x));
+const THREE = f => x => f(f(f(x)));
+const TIMES = n => f => x => n(f)(x);
+const INC = n => f => x => f(n(f)(x));
+const ADD = n => m => n(INC)(m);
+const MULT = n => m => n(ADD(m))(ZERO);
+const POWER = n => m => n(MULT(m))(ONE);
+// DEC is stolen from PRED here:
+// https://en.wikipedia.org/wiki/Lambda_calculus#Arithmetic_in_lambda_calculus
+const DEC = n => f => x => n(g => h => h(g(f)))(y => x)(y => y);
+const SUB = n => m => m(DEC)(n);
+const TRUE = x => y => x;
+const FALSE = x => y => y;
+const IF = b => b;
+const NOT = b => IF(b)(FALSE)(TRUE);
+const AND = a => b => IF(a)(IF(b)(TRUE)(FALSE))(FALSE);
+const OR = a => b => IF(a)(TRUE)(IF(b)(TRUE)(FALSE));
+const IS_ZERO = n => n(x => FALSE)(TRUE);
+const IS_LEQ = n => m => IS_ZERO(SUBTRACT(n)(m)); // we only have positive ints
+const IS_EQ = n => m => AND(IS_LEQ(n)(m))(IS_LEQ(m)(n)); // this is stupid
+// time to get recursive!
+const Y = f => (x => f(x(x)))(x => f(x(x))); // lazy recursion
+const Z = f => (x => f(_ => x(x)(_)))(x => f(_ => x(x)(_))); // eager recursion
+const FACT = Z(f => n => IF(IS_ZERO(n))(ONE)(_ => MULT(n)(f(DEC(n)))(_)));
+const DIV = null;
+const MOD = null;
+const PAIR = null;
+const LEFT = null;
+const RIGHT = null;
+const EMPTY = null;
+const UNSHIFT = null;
+const IS_EMPTY = null;
+const FIRST = null;
+const REST = null;
+const INJECT = null;
+const FOLD = null;
+const MAP = null;
+const RANGE = null;
+const SUM = null;
+const PROD = null;
+const CONCAT = null;
+const PUSH = null;
+const REVERSE = null;
+const INC_ALL = null;
+const DOUBLE_ALL = null;
+const TO_DIGITS = null;
+const TO_STRING = null;
+const FIZZBUZZ = null;
+module.exports = {
+  ZERO, ONE, TWO, THREE, TIMES, INC, ADD, MULT, POWER, DEC, SUB, TRUE,
+  FALSE, IF, NOT, AND, OR, IS_ZERO, IS_LEQ, IS_EQ, IS_LEQ, Y, Z, FACT
+};