sort method.txt

The sort method sorts the elements of an array according to the callback function.

For example:

NON-MUTATING METHOD
function nonMutatingSort(arr) {
var sortedArr = arr.slice();
return sortedArr.sort(function(a, b) {
  return a - b;
});
}
nonMutatingSort(globalArray);

JavaScript's default sorting method is by string Unicode point value, which may return unexpected results. Therefore, it is encouraged to provide a callback function to specify how to sort the array items. When such a callback function, normally called compareFunction, is supplied, the array elements are sorted according to the return value of the compareFunction: If compareFunction(a,b) returns a value less than 0 for two elements a and b, then a will come before b. If compareFunction(a,b) returns a value greater than 0 for two elements a and b, then b will come before a. If compareFunction(a,b) returns a value equal to 0 for two elements a and b, then a and b will remain unchanged.

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MUTATING METHOD - AVOID USING THIS

function ascendingOrder(arr) {
  return arr.sort(function(a, b) {
    return a - b;
  });
}
ascendingOrder([1, 5, 2, 3, 4]);
// Returns [1, 2, 3, 4, 5]

function reverseAlpha(arr) {
  return arr.sort(function(a, b) {
    return a === b ? 0 : a < b ? 1 : -1;
  });
}
reverseAlpha(['l', 'h', 'z', 'b', 's']);
// Returns ['z', 's', 'l', 'h', 'b']