iter-tools-es/impls/$equal/equal.js

The iterable toolbox

const {
  iterableCurry
} = require('../../internal/iterable.js');

const {
  __zipAll
} = require('../$zip-all/zip-all.js');

const {
  __sliceFromStart
} = require('../$slice/slice.js');

const none = Symbol('none');
const zipAllConfig = {
  filler: none
};

function __equal(iterables, same = Object.is) {
  if (iterables.length <= 1) return true;

  for (const stepValues of __zipAll(iterables, zipAllConfig)) {
    const firstValue = stepValues[0];

    for (const value of __sliceFromStart(stepValues, 1)) {
      if (!same(value, firstValue)) return false;
    }
  }

  return true;
}

exports.__equal = __equal;
const equal = /*#__PURE__*/iterableCurry(__equal, {
  minArgs: 0,
  maxArgs: 1,
  variadic: true,
  reduces: true
});
exports.equal = equal;