typescript enum default value -

i starting learn typescript aurelia framework. have implemented matthew davis's blog typescript enums in aurelia templates using viewenginehooks http://davismj.me/blog/template-constants/ aurelia's todo app.

i please set default enum value 2nd value in list , setting default 1st value in list.

also please know if {todo, priority} or {todo} needs importing shown in todo-list.ts

todo.ts

// pro tip: starting our enum @ 1, ensure values in enum truthy. export enum priority {     high = 1,     medium,     low }  export class todo {     @observable done;     //*** setting priority: priority = 2 or priority: priority = priority.medium - not change default high / 1 ***     //constructor(public list: todolist, public description: string, public priority: priority = 2, public editing: boolean = false) {      constructor(public list: todolist, public description: string, public priority: priority = priority.medium, public editing: boolean = false) {          this.list = list;         this.description = description;         //*** setting this.priority = 2 or this.priority = priority.medium - not change default high / 1 ;         //this.priority = 2;         this.priority = priority.medium;         this.editing = false;     } 

todo-list.ts

//*** {todo} or {todo, priority} needed importing? *** //import {todo} './todo'; import {todo, priority} './todo'; ...   add(description) {     if (description) {       //*** setting (this, description, 2) or (this, description, priority.medium) - not change default high / 1 ***       //this.todos.push(new todo(this, description, 2));       this.todos.push(new todo(this, description, priority.medium));       this.invalidateview();     }   } 

todo.html

<select id="priority" value.bind="type">   <option value.bind="priority[type]" repeat.for="type of prioritys">${type}</option> </select> 

as far know when declaring variable can't set default value of enum, same way number or boolean hasn't default value. however, can define default value function parameter, did in constructor (priority: priority = priority.medium), don't have supply parameter when calling constructor.

two additional notes: shouldn't this.priority = priority; this.editing = editing; instead of this.priority = priority.medium; this.editing = false;? , second, if put public in front of parameters class properties automatically added , assigned, therefore don't need additional lines of constructor. more complex classes create , assign properties manually.

concerning second question: need import priority reference enum, example when writing priority.medium. don't have import it, when compare example 2 different properties of type priority without using enum's name (for example this.todos[0].priority === this.todos[1].priority).