Build up all the logic gates from nand in js

logic-gates.js

const logicGates = {
  nand (a, b) { return !(a && b); },
  not  (a)    { return this.nand (a, a); },
  and  (a, b) { return this.not  (this.nand (a, b)); },
  or   (a, b) { return this.nand (this.not  (a), this.not(b)); },
  nor  (a, b) { return this.not  (this.or   (a, b)); },
  xor  (a, b) { return this.and  (this.nand (a, b), this.or(a, b)); },
  xnor (a, b) { return this.not  (this.xor  (a, b)); }
};

// it would be better/easier to just make prettyPrintTest a function
//  that got invoked in the template but I wanted to mess around
//  with tagged templates.
const prettyPrintTest = (...args) => args.shift().slice()
  .map((str, i) => {
    let arg = (args[i] === undefined ? '' : args[i]);
    
    if (typeof arg === 'object') {
      arg = JSON.stringify(arg)
      .replace(/:|"|\{|\}/g, ' ')
      .replace(/\s+/g, ' ')
      .replace(/true/g, 'true ')
    }
    
    return str + arg;
  }).join('');

const tests = Object.keys(logicGates)
 .map(gate => [
    { a: false, b: false },
    { a: false, b: true  },
    { a: true,  b: false },
    { a: true,  b: true  },
   ].map(test => prettyPrintTest
       `${gate}:${test}= ${(({ a, b }) => logicGates[gate](a, b))(test)}\n`)
    .join('')
  ).join('\n');

console.log(tests);

/*
  nand: a false, b false = true
  nand: a false, b true  = true
  nand: a true , b false = true
  nand: a true , b true  = false
  
  not: a false, b false = true
  not: a false, b true  = true
  not: a true , b false = false
  not: a true , b true  = false
  
  and: a false, b false = false
  and: a false, b true  = false
  and: a true , b false = false
  and: a true , b true  = true
  
  or: a false, b false = false
  or: a false, b true  = true
  or: a true , b false = true
  or: a true , b true  = true
  
  nor: a false, b false = true
  nor: a false, b true  = false
  nor: a true , b false = false
  nor: a true , b true  = false
  
  xor: a false, b false = false
  xor: a false, b true  = true
  xor: a true , b false = true
  xor: a true , b true  = false
  
  xnor: a false, b false = true
  xnor: a false, b true  = false
  xnor: a true , b false = false
  xnor: a true , b true  = true
*/

Nice one!