index.js

// Generated by CoffeeScript 2.3.2
// ![PlayFrame](https://avatars3.githubusercontent.com/u/47147479)
// # h

// ###### 0.3 kB Virtual Dom Producer

// ## Installation
// ```sh
// npm install --save @playframe/h
// ```

// ## Usage
// ```js
// import h from '@playframe/h'

// // directly
// h('a', {href: 'https://github.com/playframe/h'}, 'PlayFrame/h')

// // JSX
// const link = ()=>
//   <a href="https://github.com/playframe/h"> PlayFrame/h </a>
// ```

// ## Annotated Source

// Creating a unique Symbol for distinction between Virtual Nodes
// and plain Arrays
var VNODE, _registry, h, invoke;

VNODE = Symbol('VNODE');

_registry = {};

// Our Virtual Node is produced from a list of arguments passed
// to `h` function. Children are passed as tail of arguments,
// but any of them could be wrapped in Array

// ```js
// h('div', {class: 's'}, child1, [ child2, child3 ], child4)`)
// ```
// To achieve no runtime overhead we will avoid creating a new object
// for Virtual Node and new Array for children. We will just mark array
// of passed arguments as a `VNODE` and return it as is.
// This is compensated by a more advenced child walker used in
// [@playframe/dom](https://github.com/playframe/dom)
module.exports = h = (...a) => {
  var component, name;
  if (typeof (name = a[0]) === 'function') {
    return invoke(...a);
  } else if (component = _registry[name]) {
    a[0] = component;
    return invoke(...a);
  } else {
    a[VNODE] = true;
    return a;
  }
};

h.VNODE = VNODE;

// Registering custom components like
// `h.use({'my-component': MyComponent})`
h.use = (components) => {
  var k, v;
  for (k in components) {
    v = components[k];
    _registry[k] = v;
  }
};

// If the first argument of `h` function is a not a `'div'` but
// your Component function, we will flatten the children and attach
// them to `props`
invoke = (Component, props, ...children) => {
  var child, flat, i, len;
  if (children[0]) {
    flat = props.children = [];
    for (i = 0, len = children.length; i < len; i++) {
      child = children[i];
      if (!child[VNODE] && Array.isArray(child)) {
        flat.push(...child);
      } else {
        flat.push(child);
      }
    }
  }
  return Component(props);
};