deleight

Deleight

This is a group of 9 small libraies that simplify web frontend development using vanilla HTML, CSS and JavasSript. Deleight is an inclusive library everyone operating on the web can benefit from.

• Frontend JavaScript developers can create apps without worrying about control, modularity or maintainance. Not only is the framework flexible, modular and compact, it also aligns with familiar semantics. You still retain the convenience of a declarative API.

• Distributed frontend teams can work freely in their favourite languages without worrying about interop. HTML experts can write pure HTML. JavaScript developers can write pure JavaScript. Designers can write pure CSS. Deleight will ensure that everything plays well together. Data can be injected into HTML in multiple ways and it is not compulsory to have code tags or component specifiers in markup. The same thing also applies to style encapsulation.

• Back-end developers using any technology can stop worrying about front-end complexity. Deleight ships modern ES6 modules which can be loaded directly into webpages. Because the framework is modular and compact, you only load the libraries you need into your pages. You can also compose them with your favourite back-end template engines to reduce the number of files to load. Finally, the API is small and natural; it is very easy to pick up in a few hours.

• Ultimately users, (that is all of us), will benefit the most when all the industry practitioners have the right tools to be more productive. HTML, JavaScript and CSS are all amazinng technologies and we need to emphasize and consolidate this in modern web development.

Apart from this brief guide and the API documentation, there are also some examples which can be used to understand how the parts fit together and to develop a feel for using deleight. If you want to see the output of the exmples, you can run the included server with npm start and visit the 'examples' site at http://localhost:8000/docs/examples/index.html. The site is also hosted online here.

What follows is a brief description of the libraries and how to include them in your projects.

Appliance

Appliance provides a powerful declarative API for manipulating the DOM and for structuring code. It can be used to attach behavior to HTML elements easily and efficiently. At a basic level it can work similarly to web components without needing to create the elements. This can produce big gains in accessibility and flexibility. When used in tandem with other powerful primitives from domitory and onetomany, appiance will also match and exceed advanced component and famework functionality, like data-binding, state management and lifecycle hooks. Some things like 'hydration' are even obtained for free.

import { apply } from 'deleight/appliance'
import { mySophistry } from './my-style-manager.js'
import { meEventivity } from './my-event-manager.js'

// apply used globally on all paragraphs within the containingElement
function(containingElement) {
    apply({
        p: (...divs) => mySophistry.styles.style(...divs) || meEventivity.listener.listen('click', divs,  myEventivity.options)
    }, containingElement);  // containingElement default to document.body.
}

NB: Fully tested

Domitory

This provides a painless SQLesque API for manipulating the DOM. The library exports insert, set, update and remove (delete is a keyword in JavaScript) functions for bulk manipulation of things on the DOM. It is an efficient, consistent and simple API to use. See the examples and the API docs.

import { apply } from 'deleight/appliance'
import { set } from 'deleight/domitory'
import { range } from 'deleight/generational'

// set the text content of all selected p elements to its position in the array. We can set as many properties or attributes as we want at once.
function(containingElement) {
    apply({
        p: (...divs) => set(divs, {textContent: range(divs.length)})
    }, containingElement);
}

NB: Fully tested

Eventivity

This library provides some useful primitives for simiplifying the code that must be included in every page where JavaScript is used to support interactivity. Most JavaScript code can only run in response to an event. Eventivity exports functions for:

• composing event handlers
• creating lazy handlers whose functionality can be injected later
• promoting handler reuse with different elements
• creating fewer event hanandlers by taking advantage of event bubbling
• disabling event firing until a running handler completes including handlers that use promises.
• creating handlers for specific key events, like enter.
• creating reusable handler guards to stop event handling at any point.

It is the uninteresting but relevant bits.

import { EventListener } from 'deleight/eventivity'

export const myEventivity = {
    pClickListener: new EventListener((e, runContext) => console.log({e.target, runContext}))
};

NB: Fully tested

OneToMany

This is the API for 'reactivity'. OneToMany exports primitives to help us create and manipulate single objects which function as many objects. OneToMany provides methods for getting and setting properties on multiple objects and methods for invoking multiple functions and object methods. The library is simple, concise, explicit and transparent.

import { One, one } from "deleight/onetomany";
const arr1 = [1, 2, 3, 4, 5];

const arr2 = ["a", "b", "c", "d"];
// not compulsory to have the same length

export const oneArray = new One([arr1, arr2]);
oneArray.many.unshift([true, true, false]);
// you can add or remove arrays later using its 'many' property

const wrappedOneArray = one([arr1, arr2]);
wrappedOneArray.push([6], ["e"]);
// wrapping enables shorthand syntax like this.

NB: Fully tested

Apriori

This is a fun library to use if you need to build part or all of your DOM with the help of JavaScript. It includes primitives for template creation, template rendering and document tree building. There are primitives for building the DOM with either in-page resources or dynamically loaded ones. This gives us the flexibility to choose whatever works best for a project.

import { get, template } from "deleight/apriori";
export const myTemplate = template(await get("markup.html"));

NB: Fully tested

Sophistry

CSS is a crucial element of most pages on the web. It makes the pages beautiful and improves the UX for visual users. CSS is easy to include globally in any page. However, when localising styles with Shadow DOM (which is the officially supported method), one currently has to make the decision between writing duplicitive declarative styles vs writing JavaScript boilerplate to manage styles efficiently. Sophistry will help with efficiently scoping declaratively written styles to specific elements. The library provides an API which simplifies the code needed for such scoping. It will internally create open shadow roots where necessary. it maintains a cache to avoid reloading or re-processing the same styles (unless we request these). Sophistry can also draw styles from anywhere.

import { Sophistry } from "deleight/sophistry";
export const mySophistry = new Sophistry();
mySophistry.import("pStyle.css");

NB: Fully tested

Generational

Generational exports some useful generators to improve performance and reduce memory footprint. The range and items generators have been especially useful in the tests and examples. They may not work in many places where arrays are expected because we can only iterate them once. Thus they should be used with caution. When in doubt, just use an array.

import { range, items } from "deleight/generational";
const everyTenthIn1000 = range(0, 1000, 10);
// 0, 10, 20, ...

const everyHundredthIn1000 = items(everyTenthIn1000, range(0, 100, 10));
// 0, 100, 200, ...

NB: Fully tested

Actribute

Actribute aims to provide a more widely supported, flexible and powerful alternative to extending built-in HTML elements, using a similar API.

import { Actribute } from "deleight/actribute";

// initialize:
const fallbackProps = { 
    prop1: "Fallback", prop4: "Last resort", 
    sig: '$2b$20$o7DWuroOjbA/4LDWIstjueW9Hi6unv4fI0xAit7UQfLw/PI8iPl1y'
};
const act = new Actribute(fallbackProps);

// register components:
act.register("comp1", (node, prop1) => (node.textContent = prop1));
act.register("comp2", (node, prop2) => (node.style.left = prop2));

// use in markup:
// <section c-comp1="prop1"  c-comp2="prop2">
//     First section
// </section>

// process components:
act.process(document.body, { prop2: 1, prop3: 2 });

// unregister a component:
delete act.registry.comp2;

NB: Fully tested

Withy

We are bringing the with functionality back to JavaScript with the help of Proxies. With was removed from the language because of performance, code comprehension and readbility issues. Once we have an implementation without these limitations, we can benefit from the improved concision and structure of our code.

import { With, SET } from "deleight/withy";
With(document.createElement('div'))[SET]({
    textContent: 'Wow!'
})(div => document.body.append(div));

NB: Fully tested

Installation

You can currently install deleight in 2 ways:

Direct download

Download or clone the repository and import any libraries you need from the ./src. It contains both JavaScript and TypeScript files.

From NPM

npm i deleight

Deleight will also be installable from a CDN network soon.

Usage

Depending on how you bring deleight into your app, there may be subtle differences in how to import the libraries:

Direct download

import { apply } from "./deleight/src/appliance.js";
import { One } from "./deleight/src/onetomany.js";
// ...

From NPM

import { apply } from "deleight/appliance";
import { One } from "deleight/onetomany";
// ...

Contributing

If you like the concept and/or the direction of deleight, feel free to contribute to this project. We are accepting contributions in many areas. Just give us a shout. The discussion area is open, and more channels are in the pipeline.

You can also sponsor this project. That is also in the works. For now you can give us a shout.

Thank you for contributing.

Ongoing work

• Adding and completing examples

Ideas

• Progressive Web Apps
• Efficient navigation