old_contents: #!/usr/bin/env node
  
  let variable = 4;
  console.assert(typeof variable === "number");
  console.log("4: " + variable + " ## " + typeof variable);
  
  variable = 1.1415;
  console.log(variable);
  console.assert(typeof variable === "number");
  console.log("1.1415: " + variable + " ## " + typeof variable);
  
  variable = 2 / 7;
  console.assert(typeof variable === "number");
  console.log("2 / 7: " + variable + " ## " + typeof variable);
  
  variable = 2 % 7;
  console.assert(typeof variable === "number");
  console.log("2 % 7: " + variable + " ## " + typeof variable);
  
  variable = Math.PI;
  console.assert(typeof variable === "number");
  console.log("Math.PI: " + variable + " ## " + typeof variable);
  
  variable = Math.E;
  console.assert(typeof variable === "number");
  console.log("Math.E: " + variable + " ## " + typeof variable);
  
  variable = Number.EPSILON;
  console.assert(typeof variable === "number");
  console.log("Number.EPSILON: " + variable + " ## " + typeof variable);
  
  variable = Number.MAX_SAFE_INTEGER;
  console.assert(typeof variable === "number");
  console.log("Number.MAX_SAFE_INTEGER: " + variable + " ## " + typeof variable);
  
  variable = Number.MAX_VALUE;
  console.assert(typeof variable === "number");
  console.log("Number.MAX_VALUE: " + variable + " ## " + typeof variable);
  
  variable = Number.MIN_SAFE_INTEGER;
  console.assert(typeof variable === "number");
  console.log("Number.MIN_SAFE_INTEGER: " + variable + " ## " + typeof variable);
  
  variable = Number.MIN_VALUE;
  console.assert(typeof variable === "number");
  console.log("Number.MIN_VALUE: " + variable + " ## " + typeof variable);
  
  variable = Number.POSITIVE_INFINITY;
  console.assert(typeof variable === "number");
  console.log("Number.POSITIVE_INFINITY: " + variable + " ## " + typeof variable);
  
  variable = Number.NEGATIVE_INFINITY;
  console.assert(typeof variable === "number");
  console.log("Number.NEGATIVE_INFINITY: " + variable + " ## " + typeof variable);
  
  variable = Number.NaN;
  console.assert(typeof variable === "number");
  console.log("Number.NaN: " + variable + " ## " + typeof variable);
  
  console.assert(Math.PI === Math.PI);
  console.assert(Number.POSITIVE_INFINITY === Number.POSITIVE_INFINITY);
  console.assert(Number.POSITIVE_INFINITY === 7 / 0);
  variable = 7 / 0;
  console.log("7 / 0: " + variable + " ## " + typeof variable);
  variable = -7 / 0;
  console.log("-7 / 0: " + variable + " ## " + typeof variable);
  console.assert(Number.NaN !== Number.NaN);
  console.assert(Number.NaN !== 0 / 0);
  console.assert(Number.isNaN(Number.NaN));
  console.assert(Number.isNaN(0 / 0));
  variable = 0 / 0;
  console.log("0 / 0: " + variable + " ## " + typeof variable);
  
new_contents: #!/usr/bin/env node
  
  let variable = 4;
  console.assert(typeof variable === "number");
  console.log("4: " + variable + " ## " + typeof variable);
  
  variable = 1.1415;
  console.log(variable);
  console.assert(typeof variable === "number");
  console.log("1.1415: " + variable + " ## " + typeof variable);
  
  variable = 2 + 7;
  console.assert(typeof variable === "number");
  console.log("2 + 7: " + variable + " ## " + typeof variable);
  
  variable = 2 - 7;
  console.assert(typeof variable === "number");
  console.log("2 - 7: " + variable + " ## " + typeof variable);
  
  variable = 2 * 7;
  console.assert(typeof variable === "number");
  console.log("2 * 7: " + variable + " ## " + typeof variable);
  
  variable = 2 / 7;
  console.assert(typeof variable === "number");
  console.log("2 / 7: " + variable + " ## " + typeof variable);
  
  variable = 2 % 7;
  console.assert(typeof variable === "number");
  console.log("2 % 7: " + variable + " ## " + typeof variable);
  
  variable = Math.PI;
  console.assert(typeof variable === "number");
  console.log("Math.PI: " + variable + " ## " + typeof variable);
  
  variable = Math.E;
  console.assert(typeof variable === "number");
  console.log("Math.E: " + variable + " ## " + typeof variable);
  
  variable = Number.EPSILON;
  console.assert(typeof variable === "number");
  console.log("Number.EPSILON: " + variable + " ## " + typeof variable);
  
  variable = Number.MAX_SAFE_INTEGER;
  console.assert(typeof variable === "number");
  console.log("Number.MAX_SAFE_INTEGER: " + variable + " ## " + typeof variable);
  
  variable = Number.MAX_VALUE;
  console.assert(typeof variable === "number");
  console.log("Number.MAX_VALUE: " + variable + " ## " + typeof variable);
  
  variable = Number.MIN_SAFE_INTEGER;
  console.assert(typeof variable === "number");
  console.log("Number.MIN_SAFE_INTEGER: " + variable + " ## " + typeof variable);
  
  variable = Number.MIN_VALUE;
  console.assert(typeof variable === "number");
  console.log("Number.MIN_VALUE: " + variable + " ## " + typeof variable);
  
  variable = Number.POSITIVE_INFINITY;
  console.assert(typeof variable === "number");
  console.log("Number.POSITIVE_INFINITY: " + variable + " ## " + typeof variable);
  
  variable = Number.NEGATIVE_INFINITY;
  console.assert(typeof variable === "number");
  console.log("Number.NEGATIVE_INFINITY: " + variable + " ## " + typeof variable);
  
  variable = Number.NaN;
  console.assert(typeof variable === "number");
  console.log("Number.NaN: " + variable + " ## " + typeof variable);
  
  console.assert(Math.PI === Math.PI);
  console.assert(Number.POSITIVE_INFINITY === Number.POSITIVE_INFINITY);
  console.assert(Number.POSITIVE_INFINITY === 7 / 0);
  variable = 7 / 0;
  console.log("7 / 0: " + variable + " ## " + typeof variable);
  variable = -7 / 0;
  console.log("-7 / 0: " + variable + " ## " + typeof variable);
  console.assert(Number.NaN !== Number.NaN);
  console.assert(Number.NaN !== 0 / 0);
  console.assert(Number.isNaN(Number.NaN));
  console.assert(Number.isNaN(0 / 0));
  variable = 0 / 0;
  console.log("0 / 0: " + variable + " ## " + typeof variable);
  
  console.log("4^12", Math.pow(4, 12));
  console.log("sqrt 12", Math.sqrt(12));
  console.log("random", Math.random());
  
subject: Add number operations