Ember-option

Ever wanted to use Options in ember, well this addon gives you exactly that ability. Say goodbye to null checking your data, and hello to monadic composition.

Usage

Simply import this addon, and it will add getAsOption('key') to the Ember.Object class.

Null Checking

const Obj = Ember.Object.extend({

  foo: 'foo',
  bar: 'bar',
  baz: 'baz',
  
  /**
    * @returns {null|string}
    */   
  someFunction() {
    const foo = this.get('foo');
    const bar = this.get('bar');
    const baz = this.get('baz');
    const qux = '';
  
    if (foo !== null && bar !== null && this.get('baz'){
        qux = foo + bar + baz; 
    }
    
    return qux;
  }
});

Obj.create({
  foo: 'foo',
  bar: 'bar',
  baz: 'baz',
}).someFunction() // returns a string


Obj.create({
  foo: null,
  bar: null,
  baz: null,
}).someFunction() // likely returns a NPE 

The above code encourages propgation of nulls, which can lead to all kinds of trouble.

Options

// using options (I'd kill for a for comprehension)

Ember.Object.extend({

  foo: 'foo',
  bar: 'bar',
  baz: 'baz',

  /**
    * @returns {Option.<string>}
    */   
  someFunction() {
    return this.getAsOption('foo')
            .flatMap(foo => 
              this.getAsOption('bar')
                .flatMap(bar => 
                  this.getAsOption('baz').map(baz => foo + bar + baz) 
                )
            )
  }
});

let maybeString Obj.create({
  foo: 'foo',
  bar: 'bar',
  baz: 'baz',
}).someFunction(); // returns Option.<string>

maybeString.valueOrElse('foo') // foobarbaz

let maybeString2 = Obj.create({
  foo: null,
  bar: null,
  baz: null,
}).someFunction() // None
 
maybeString2.valueOrElse('something went wrong') // something went wrong

Contributors

• Joe Gaudet - [email protected]
• Kenneth Buck - [email protected]

Shout Outs

• Martin Odersky (I was a scala dev once)
• mwilliamson https://github.com/mwilliamson/node-options