maia-util/es6/array_equals.js

Utility math and music functions supporting various applications by Music Artificial Intelligence Algorithms, Inc.

export default function array_equals(arr,arr2){
  // Joe on Stack Overflow 27/12/2014.
  // In
  // array Array mandatory
  // Out Boolean
  // Returns true if two arrays are equal, and false otherwise.
  // http://stackoverflow.com/questions/7837456/comparing-two-arrays-in-javascript

  // If the other array is a falsy value, return.
  if (!arr2)
  return false;

  // Compare lengths.
  if (arr.length != arr2.length)
  return false;

  for (let i = 0, l=arr.length; i < l; i++){
    // Check if we have nested arr2s.
    if (arr[i] instanceof Array && arr2[i] instanceof Array){
      // Recurse into the nested arr2s.
      if (!array_equals(arr[i],arr2[i]))
      return false;
    }
    else if (arr[i] != arr2[i]){
      // Warning - two different object instances will never be equal:
      // {x:20} != {x:20}.
      return false;
    }
  }
  return true;
}