Function addNumericalSeparator

lib/internal/errors.js:883–891

(val)

// Only use this for integers! Decimal numbers do not work with this function.
function addNumericalSeparator(val) {
  let res = '';
  let i = val.length;
  const start = val[0] === '-' ? 1 : 0;
  for (; i >= start + 4; i -= 3) {
    res = `_${StringPrototypeSlice(val, i - 3, i)}${res}`;
  }
  return `${StringPrototypeSlice(val, 0, i)}${res}`;
}

// Used to enhance the stack that will be picked up by the inspector
const kEnhanceStackBeforeInspector = Symbol('kEnhanceStackBeforeInspector');