README

Multitest

A small library for sorting arrays by multiple criteria.

Installation

npm install multisort --save

bower install multisort --save

Basic Usage

var input = [
  {firstName: "Kate", lastName: "Bush"},
  {firstName: "George", lastName: "Bush", suffix: "Junior"},
  {firstName: "George", lastName: "Orwell"},
  {firstName: "George", lastName: "Bush", suffix: "Senior"},
];

var criteria = [
  'firstName',
  '~lastName.length',
  'suffix.charAt(1)'
];

multisort(inputArray, criteria)

// input is now sorted by firstName (ascending), then lastName.length (descending),
// and finally suffix.charAt, called with 1 as the argument:
// [
//  {firstName: "George", lastName: "Orwell"},
//  {firstName: "George", lastName: "Bush", suffix: "Senior"},
//  {firstName: "George", lastName: "Bush", suffix: "Junior"},
//  {firstName: "Kate", lastName: "Bush"},
// ];

var input = [8, 7, 6, 5, 4, 3, 2, 1];

var criteria = [
  function(a) {return a % 2},
  function(a) {return a % 3},
  function(a) {return a}
];

multisort(input, criteria);

// input is now:
// [6, 4, 2, 8, 3, 1, 7, 5]

Partial Application

// Passing a single argument makes a sorting function that can then be applied to lists.
var sortByMod2AndMod3 = multisort([
  function(a) {return a % 2},
  function(a) {return a % 3},
  function(a) {return a}
]);

var input1 = [8, 7, 6, 5, 4, 3, 2, 1];
sortByMod2AndMod3(input1);
// input1 is [6, 4, 2, 8, 3, 1, 7, 5]

var input2 = [1, 5, 10, 25, 50, 100];
sortByMod2AndMod3(input2);
// input2 is [10, 100, 50, 1, 25, 5]

Features

Criteria types:

Function: Applies the given function to each element, and the return values are sorted in ascending order, using < and >.
String: Picks out the property indicated by the string, and sorts in ascending order, using < and >. Nested properties can be accessed with dot syntax, as in "property.subproperty.subsubproperty"
!String or ~String: As above, but sorted in descending order. This works with the functional and existential operators below.
String(arg1, arg2...): As above, but calls the indicated property as a function with the given arguments. Arguments are split by commas, trimmed, and parsed with JSON.parse.
String?: As above, tests whether the property is null or undefined. Items without the property are sorted before items with it.

Tests

npm test

Contributing

In lieu of a formal styleguide, take care to maintain the existing coding style. Add unit tests for any new or changed functionality. Lint and test your code.

Release History

0.1.0 Initial release

Usage no npm install needed!