Show HN: Elementree, Create Web UIs with Proxy Observables and Template Literals
GitHub - mjstahl/elementree: Create Web UIs with Proxy Observables and JS Template Literals
   
Elementree

"Celebrate the code of the problem domain as opposed to the framework."

Elementree is an extremely small front-end JavaScript "framework" with a focus
on getting the job done with the mimimum amount of framework-y concepts.
Example
<!DOCTYPE html>
<html>
  <body>
    <script type="module">
      import { merge, prepare, render } from 'https://unpkg.com/elementree'

      function View (state) {
        if (!state.email) state.requestUser()
        return render`
          <body>
            <p>Hello! ${state.email}</p>
            <button onclick=${() => state.nextEmail()}>Next Email</button>
          </body>
        `
      }

      const State = {
        id: 1,
        email: '',
        nextEmail() {
          this.email = null
          this.id += 1
        },
        async requestUser() {
          const response = await fetch(`https://reqres.in/api/users/${this.id}`)
          const { data } = await response.json()
          this.email = data.email
        }
      }
      merge('body', prepare(View, State))
    </script>
  </body>
</html>
Elementree API
merge(to: String, view: Function [, state: Object]) -> undefined
merge wires up a view and an optional object representing the application
state and merges it to a selector. Simply put, merge renders your root view to the DOM.
The first argument to merge is a string which will be used by document.querySelector, after DOMContentLoaded, to find root element. The second argument is the top-level view. This argument is a Function that returns a function that returns an HTMLElement such as a prepare call. The third, optional, argument is an object representing the application's state. This object will passed to the renderer function as an parent argument (i.e. following the view's state if there is one).
Elementree adds a single property to the application's state object. The route property is a concatenation of location.pathname, location.search and location.hash. Updating the route property will cause a history.pushState. Updating the address through browser interations will update the route property.
If the window object does not exist the call to merge will return the outerHTML on the result of the rendering.
prepare(template: Function [, state: Object]) -> (Function -> HTMLElement)
prepare a template function with a state object, creating a view function. At a minimum, a template function is required to be passed as the first argument. The second argument, which is optional, is an object representing the local view state. If the template function is joined with a state, the state object will ALWAYS be the 0th argument to the view function. All parent arguments will follow.
render`template: String` -> HTMLElement
A tagged template function. Turn a JavaScript template string into an HTMLElement. If the template has more than one root element a DocumentFragment is returned.
html`unescaped: String` -> HTMLElement
Use html to interpolate HTML, without escaping it, directly into your template.
Attribution
This project would suck a whole lot more without the input from my awesome co-workers at Bitovi, the inspiration from @choojs, and the amazing packages from @sindresorhus. Thank you.
