Vasille Less Library

Vasille less library is frontend solution for safe, fast & powerful applications.

Table of content

• Installation
• How to use Vasille
• How SAFE is Vasille
• How FAST is Vasille
• How POWERFUL is Vasille
• Best Practices

Installation

npm install vasille --save
npm install vasille-less --save
npm install vasille-magic --save

How to use Vasille

There are several modes to use Vasille.

Documentation for beginners (how to create the first project step by step):

• Vasille Core Library - the hard way - low-level
• Vasille Less Library - perfect for me - high-level
• Vasille Magic - perfect for you - highest-level

Full documentation:

• Vasille Core Library API- write anything - low-level
• Vasille Less Library API- write less do more - high-level
• Vasille Magic API- compiler writes for you - highest-level

Getting ready be example

• TypeScript Example
• JavaScript Example (Vasille Magic not supported)
• Flow.js Example (Vasille Magic not supported)

How SAFE is Vasille

The safe of your application is ensured by

• 100% coverage of vasille code by unit tests. Each function, each branch are working as designed.
• strong typing makes your javascript/typescript code safe as C++ code. All entities of vasille core library are strong typed, including:
  • data fields & properties.
  • computed properties (function parameters & result).
  • methods.
  • events (defined handlers & event emit).
  • DOM events & DOM operation (attributing, styling, etc.).
  • slots of component.
  • references to children.
• What you write is what you get - there is no hidden operations, you can control everything.
• No asynchronous code, when the line of code is executed, the DOM and reactive things are already synced.

How FAST is Vasille

The test project was coded using the next frameworks:

• Angular / Try Initial / Try Optimized.
• React / Try Initial / Try Optimized.
• Vue 2 / Try Initial / Try Optimized.
• Vue 3 / Try Initial / Try Optimized.
• Svelte / Try Initial / Try Optimized.
• Vasille / Try Initial / Try Optimized.

The result of test are demonstrated in figures 1 & 2. The test result are measured in FPS (frames per second), which is calculated as 1000 / ft, where ft is an average frame time in ms of 20 frames. All values are absolute. Higher is better.

The initial version is updating all the page content in each frame. The page reactivity connections are very complex, and we get poor results in Angular, React, Vue & Svelte.

The optimized version disables the offscreen & non-actual content, which simplifies the reactivity complexity in time. Angular & Svelte give result similar to Vasille. React & Vue continue to be slow in the beginning of test.

Conclusion: The reactivity system of Vasille is very fast and its complexity is not slowing down the application.

Figure 1: Initial version

Figure 2: Optimized version

How POWERFUL is Vasille

The secret of Vasille is a good task decomposition. The core library is composed of an effective reactive module and a DOM generation engine based on it.

Reactivity Module

Reactivity module is used to create a model of data. It can contain self-updating values, forward-only shared data. Reactivity of objects/fields can be disabled/enabled manually.

• Destroyable is an entity which has a custom destructor.
• IValue<T> is a common interface for any value container, with next members:
  • get $ gets the encapsulated value.
  • set $ manually update the encapsulated value, if enabled triggers updating of all linked data.
  • disable disables the reactivity.
  • enable enables the reactivity and triggers updating of all linked data.
• Reference<T> contains a value of type T.
• Mirror<T> syncs self value with another IValue container, can be used to share a value forward-only.
• Pointer<T> same as Mirror, but it can switch between IValue target anytime.
• Expression<ReturnType, Args...> is a self-updating value.
• Reactive is a reactive object which can have multiple reactive fields, emit/receive events/signals.

DOM Generation Engine

DOM Generation Engine is used to describe a virtual DOM of reactive fragments, which will be reflected into a browser DOM and keep up to date it.

• Fragment describes a virtual DOM node, which has siblings, children, parent & slots.
• TextNode reflects a Text node.
• INode reflects a Element node.
• Tag reflect a self created Element node.
• Extension reflects an existing Element node.
• Component reflects a Element node created by a Tag child.
• AppNode is root of a Vasille application, can be used to create applications in application.
• App is root of a definitive Vasille application.
• DebugNode reflects a Comment node, useful for debug.
• Watch recompose children nodes on model value change.
• RepeatNode creates multiples children nodes using the same code multiple time.
• BaseView represent a view in context of MVC (Model-View-Controller).
• ObjectView repeats slot content for each value of ObjectModel.
• MapView repeats slot content for each MapModel value.
• SetView repeats slot content for each SetModel value.
• ArrayView repeats slot content for each ArrayModel value respecting its order.

CDN

ES2015 version
<script src="https://unpkg.com/vasille"></script>
ES5 Compatible version
<script src="https://unpkg.com/vasille/cdn/es5.js"></script>

Flow.js typedef

Add the next lines to [libs] section in your .flowconfig file

node_modules/vasille/flow-typed
node_modules/vasille-less/flow-typed
node_modules/vasille-magic/flow-typed

Best Practices applicable to Vasille Core Library

• Reactive Object Practice
• Application
• Application in Application
• Signaling
• Forward Only Data Exchange
• Absolute, Relative & Auto Values
• Signaling Intercepting
• Debugging
• Fragment vs Component
• Extensions
• Model-View-Controller

Questions

If you have questions, fell free to contact the maintainer of project:

• Author's Email
• Project Discord Server
• Author's Telegram
• Author's VK