enum-expansion

Enum

Classed Based Enum implementation

100% Typed
Easy to Expand

Background

Since Typescript Enum is really simple almost like a primary Data Type,
There are eager for a Standard but also extendable Enum Type

Insprired By Swift Language
SourceCode Highly Inspired By Dr. Axel Rauschmayer : Enum Pattern

Installation

npm install enum-expansion

Example

1. Declare Enum

export class TaskStatus extends Enum {
  static wip = new TaskStatus('1', 'WIP')
  static working = new TaskStatus('2', 'Working')
  static done = new TaskStatus('3', 'Done')
  static error = new TaskStatus('4', 'Error')
  static _ = TaskStatus.closeEnum()
  constructor(value: string, label: string) {
    super()
    this.value = value
    this.label = label
  }
}

2. Use Enum

1. convert value to enum instance : const TaskStatus = TaskStatus.of(1)
2. get keys : TaskStatus.keys
3. get values: TaskStatus.values
4. get [{value, label}] options to render View : const options = TaskStatus.options()
5. get Enum label : TaskStatus.wip.label
6. get Enum Value : TaskStatus.wip.value
7. compare : if(someVar === TaskStatus.wip.value) { ... }

3. Expand Enum

Expand Props and Functions

export class TaskStatus extends Enum {
  static wip = new TaskStatus('1', 'WIP', '#ff00ff');
  static working = new TaskStatus('2', 'Working', '#ffffff');
  static done = new TaskStatus('3', 'Done', '#ffff00');
  static error = new TaskStatus('4', 'Error', '#000000');

  static _ = TaskStatus.closeEnum();

  public color!: string; // 1. Declare Expand Props

  // 2. Update constructor
  constructor(value: string, label: string, color: string) {
    super();
    this.value = value;
    this.label = label;
    this.color = color;
  }

  // 4. Decalre Expand Function
  public getIcon(){
    return {"wip": 'wip.png', 'error': 'error.png'}[this.label] || 'default.png'
  }

  public performAction(taskId: string){
      switch (this) {
        case TaskStatus.wip:
          return fetch(`/markDone`, {method: 'POST', body: JSON.stringify({id: taskId})})
        case TaskStatus.working:
          // ...logic
          break
        case TaskStatus.done:
          // ...logic
          break
        case TaskStatus.error:
          // ...logic
          break
        default:
          break
      }
  }
}