What's been fixed?
- Missing imports and properties added
- Forgotten this. to variables added
- Unused declarations removed
- Abstract members implemented
What is new in Microsoft TypeScript 2.2?
- Support for ECMAScript 2015 mix-in class pattern with rules for blending regular construct signatures with mix-in construct signatures in intersection types;
- The new object type to match any types, except for primitive ones, like string, boolean, symbol, number, null, undefined;
- The new.target support (ES2015 new syntax);
- Improved checking for undefined / null in operands of expressions;
- Dotted property for types with string index signature allowed at TypeScript version 2.2;
- Added support for spread operator on JSX element children;
- New react-native mode that keeps the JSX syntax in the output file, but gives it a .js extension, as React Native loader requires;
- Enhanced string indexing behavior to make testing JSON object properties more ergonomic;
And what's next?
Currently, MS team is already working on the TypeScript 2.3 that is planned for release in May 2017. For now, it is made up of:
- Generic defaults
- Asynchronous iterators support
- Generator support for ES5 / ES3
- JSX stateless components overload resolution
However, it is still a brief preview. You can check out MS TypeScript 2.2 by installing it from npm:
<code>npm install -g typescript</code>