Introduction

Useful lib for managing range list.

What is Range List:

A range list is an aggregate of these ranges: [1, 5), [10, 11), [100,201);

What is Range

Range: A pair of integers define a range, for example: [1, 5).
This range includes integers: 1, 2, 3, and 4.

public behaviors

1. add behavior

   add a range into range list.
   if there is no overlap ranges in range list, just add range into list.
   if there are one or more overlap ranges in range list, remove existing overlapped ranges in the range list, and put the merged range into range list.
   every time before adding range, it will validate if the range to be added correct.

2. remove behavior

   remove a range from range list.
   if there is no range in range list match the range to be removed, then keep range list unchanged.
   if there is any overlap area between the range to be removed,
   and the ranges in range list, then remove the overlap part and split ranges to small ranges if possible.

3. print behavior

   print range list according to the format.
   the format is as below:
   [10,20) [30, 40)
   the function will cache the printed string when there is no modification to range list.

Usage

npm install j-range-list-js

// ---------------------------
// cjs: 
const RangeList = require('j-range-list-js').default;

// esm:
import RangeList from 'j-range-list-js';


const rl = new RangeList();
rl.add([1, 5]);
rl.print();
// Should display: [1, 5)
rl.add([10, 20]);
rl.print();
// Should display: [1, 5) [10, 20)
rl.add([20, 20]);
rl.print();
// Should display: [1, 5) [10, 20)
rl.add([20, 21]);
rl.print();
// Should display: [1, 5) [10, 21)
rl.add([2, 4]);
rl.print();
// Should display: [1, 5) [10, 21)
rl.add([3, 8]);
rl.print();
// Should display: [1, 8) [10, 21)
rl.remove([10, 10]);
rl.print();
// Should display: [1, 8) [10, 21)
rl.remove([10, 11]);
rl.print();
// Should display: [1, 8) [11, 21)
rl.remove([15, 17]);
rl.print();
// Should display: [1, 8) [11, 15) [17, 21)
rl.remove([3, 19]);
rl.print();
// Should display: [1, 3) [19, 21)
 

Development

Plain js with FlowJS.
Develop functions following flow js
recommend: test first (TDD). Make sure your code coverage is enough(>=90%, best to have 100%).
use 'yarn test' to check the coverage

src folder: for source code development.
lib folder: minified code which can be used as library module
test folder: test cases

Git

master branch for production release version
develop branch for QA release version
feature branch for feature development

make sure squash merge feature to develop branch

Publish

Before publish, you should make sure thins as below:

1. change .npmrc registry: registry.yarnpkg.com
2. make sure you have logged in
3. make sure all new changes has been merged to master branch, and you have checked out to master branch.