Boolean State

[cowboyd]

The microstate primitive Bool wraps a simple boolean value.

No matter what you pass to the constructor, it is naturally coerced into a boolean value:

new Bool(true).valueOf() //=> true
new Bool(false).valueOf() //=> false
new Bool("Ohai") //=> true
new Bool(null) //=> false

The same applies if you set a boolean value to explicit value:

new Bool(false).set("Ohai").valueOf() //=> true
new Bool(true).set(null).valueOf() //=> false

The only other transition available on a boolean value is toggle:

new Bool(true).toggle().valueOf() //=> false
new Bool(false).toggle().valueOf() //=> true

[taras]

@cowboyd for new Bool(false).set("Ohai").valueOf(), does the value become Ohai or is it coerced to a boolean at creation?

[cowboyd]

You've pointed to an important use-case

new Bool(false).set("Ohai").valueOf() //=> true

It will be coerced in the sense that all values passed to set are passed as arguments to the "constructor" function. Don't know what the syntax will be yet, but probably:

const Bool = State.extend({
  construct(value) {
    return !!value;
  }
});

[taras]

you mean, constructor(value) { return !!value; } right?

I tried to implement Bool but it doesn't seem to call the constructor function yet. Is there something missing from implementation to do this yet?

[cowboyd]

Yes, it has not been added yet, so you will have to coerce the value manually for now. We could call it constructor, but I am a bit worried that it might be confused as the es6 constructor, and it does need a return value.

[cowboyd]

initialize(), box(), coerce() might be other options.