New JavaScript Language Service "Salsa" is available in Visual Studio "15" Preview

New JavaScript Language Service "Salsa" is available in Visual Studio "15" Preview. It is used for providing syntax highlighting, completion lists, signature help, and other tooling features for a specific language inside the IDE.

What is TypeScript?
It is a strict superset of JavaScript, and adds optional static typing and class-based object-oriented programming to the language.

Salsa is powered by the same static analysis that provides type inference in TypeScript. Salsa is not enabled by default.  To enable Salsa in Visual Studio “15” Preview, save the below snippet as a local file named salsa.reg, run it to update the registry, and then restart Visual Studio.

Windows Registry Editor Version 5.00
[HKEY_CURRENT_USER\SOFTWARE\Microsoft\VisualStudio\15.0\TypeScriptLanguageService]
"UseTypeScriptExperimental"=dword:00000001

New features provided by Salsa

• ES6 and commonjs modules
• JSX support
• Types from TypeScript definitions
• Planned Features
• Notable Changes

For more details you can read the original blog post by Microsoft.