src/harmony-math.js

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'use strict';

// ES6 draft 09-27-13, section 20.2.2.28.
function MathSign(x) {
  x = TO_NUMBER_INLINE(x);
  if (x > 0) return 1;
  if (x < 0) return -1;
  if (x === 0) return x;
  return NAN;
}


// ES6 draft 09-27-13, section 20.2.2.34.
function MathTrunc(x) {
  x = TO_NUMBER_INLINE(x);
  if (x > 0) return MathFloor(x);
  if (x < 0) return MathCeil(x);
  if (x === 0) return x;
  return NAN;
}


function ExtendMath() {
  %CheckIsBootstrapping();

  // Set up the non-enumerable functions on the Math object.
  InstallFunctions($Math, DONT_ENUM, $Array(
    "sign", MathSign,
    "trunc", MathTrunc
  ));
}

ExtendMath();