Undefined Parameter Causes Crash

Broken Code

const { h, app } = hyperapp
/** @jsx h */

const Example = ({a}) =>
	<div>
		Item {a}
	</div>

app({ 
    model: "Hi.", 
    view: model => <div><Example/>this should always render</div>
})

TypeError: undefined is not an object (evaluating ‘node.data’)

Working Code

const { h, app } = hyperapp
/** @jsx h */

const Example = ({a}) =>
	<div>
		Item {a}
	</div>

app({ 
    model: "Hi.", 
    view: model => <div><Example a=""/>this should always render</div>
})

---

Again, I’m not sure if this is intentional or a bug. Might be nice to show a better error if the ENV isn’t production in case this is intended.

[tunnckoCore]

Btw reference https://facebook.github.io/react/docs/jsx-in-depth.html#booleans-null-and-undefined-are-ignored

[jorgebucaran]

@dodekeract Fortunately this is somewhat related to https://github.com/hyperapp/hyperapp/issues/92, so fixing this might kill two birds with one stone.