This project uses the Closure Compiler to parse Closure-style JSDoc type annotations from ES5/ES2015 code, and generates a suitable TypeScript type definition file (.d.ts) for the exported API.

The intent is to allow TypeScript code to re-use libraries written with Closure-style type declarations, and still benefit from type checking in the TypeScript compiler and IDE tooling for highlighting errors and type-sensitive auto-complete.

We don't offer a binary distribution, so first you need to build:

$ gradle build installDist
...
BUILD SUCCESSFUL

You can use Clutz as a library from a Java based build, or execute the wrapper script produced by Gradle:

$ PATH=$PATH:./build/install/clutz/bin
$ clutz --externs src/resources/es6_min.js -o out.d.ts path/to/my/sources.js

This creates TypeScript type definitions in out.d.ts for all the closure types discovered in the inputs. Symbols which were declared with goog.provide('x') may be imported as import x from 'goog:x';. For full explanation of what TypeScript types are produced for different Closure usages, see the .js and .d.ts files in src/test/com/google/javascript/clutz.

When compiling TypeScript code that depends on the closure code, include the src/resources/closure.lib.d.ts along with out.d.ts.

Note that clutz requires that your code can be compiled with Closure Compiler. If you get errors, try reproducing them without clutz, just compiling your code with Closure. You can find the options we pass to Closure Compiler in src/main/java/com/google/javascript/clutz/Options.java. If the failure is reproducible this way, then you have a mistake in your code (or a bug in Closure Compiler).

Clutz produces declaration files that are guaranteed to be accepted by a version of TypeScript newer than ac6224d6. The current test suite runs against typescript@next, so that is always a good choice.