yantra

JavaScript Engine for .NET Standard

yantrajs
27
0
JavaScript

YantraJS

Yantra (Machine in Sanskrit) is a Managed JavaScript Engine for .NET (Core and Standard 2) written completely in C#.

NuGet

Name Package
YantraJS (With CSX Module Support) NuGet
YantraJS.Core (Compiler) NuGet
YantraJS.ExpressionCompiler (IL Compiler) NuGet
Yantra JS.ModuleExtensions (Fluent interface for module registration) Nuget

Features

  1. Compiles JavaScript to .Net Assembly
  2. Strict Mode Only JavaScript*
  3. Arrow functions
  4. Classes
  5. Class members
  6. Enhanced object literals
  7. Template strings and tagged templates
  8. Destructuring
  9. let const
  10. Map, Set, WeakMap, WeakSet
  11. Symbols
  12. Subclassable built-ins
  13. Binary and Octal literals
  14. Module support
  15. Null coalesce
  16. Optional property chain identifier?.[], identifier?.(, identifier?.identifier
  17. Rest, Default and Spread Parameters
  18. Generators, iterators, for…of
  19. Async/Await
  20. Optional parameters
  21. Tail call optimization
  22. Many ES5 + ES6 features
  23. CommonJS & ES6 Module Support
  24. Easily marshal CLR Object to JavaScript and other way around
  25. CSX Module support
  26. Mixed module system, YantraJS supports require and import.
  27. Explicit resource management with using and await using keywords.
  28. AOT ready (Source Generators have been used for loading Runtime Objects).

* Most JavaScript today is available in strict mode, we do not feel any need to support non strict mode as modules are strict by default.

Mixed modules

Currently YantraJS supports Both CommonJS and ES modules without any extra work, with little trick, module resolution is node like. Module loader loads module asynchronously, so import will work without any extra effort. However, require will run AsyncPump to wait till the module is loaded correctly. Unless you do some multithreading, mixed modules will not lead to any deadlocks.

Module loading order,

  • Module names may or may not have extensions.
  • File will be loaded if same name exists on disk.
  • Engine will try to load ${name}.csx file, if it exists it will load the module.
  • Engine will then try to load ${name}.js file, if it exits it will load the module.
  • Otherwise it will travel to parent directory and search modules in node_modules folder in exact same order defined earlier.

Roadmap

As we often have difficulty in writing cross environment scripts (browser and process such as node), we want to first implement basic common features on both.

  1. Next in plan is Network API, Simple fetch is available in YantraContext, we will focus on adding Stream API.
  2. Unified API to access system resources through JavaScript modules that dynamically utilize .NET objects.
  3. Add node modules compatibility.
  4. V8 Protocol Implementation is in progress.

Documentation

  1. Introduction
  2. Expression Compiler
  3. JavaScript Engine

Discussions

We recommend using Github Discussion on this repository for any question regarding this product.

Special Thanks

  1. We are thankful to authors of Jurassic (we have incorporated number parser, promise and some unit tests from Jurassic.) https://github.com/paulbartrum/jurassic
  2. We are thankful to authors of EsprimaDotNet, we initially built prototype over EsprimaDotNet, but we chose to build our parser/scanner from scratch to support token spans. https://github.com/sebastienros/esprima-dotnet
  3. We are thankful to author of ILPack (we have incorporated saving IL to Assembly from this library.) https://github.com/Lokad/ILPack