• Frequently asked questions.
  • Table of Contents
  • Unexpected Output
  • Using Closure Compiler
  • Contributions
  • Design of Closure Compiler
  • Unexpected Output
  • My multi-line goog.require statements are getting ignored
  • The compiler crashes with UnsupportedClassVersionError or Unsupported major.minor version 51.0 or NoSuchMethodError
  • I get a "Trailing comma is not legal" error. But it works on Firefox!
  • I get "invalid property id" errors. But it works on Firefox!
  • I get "Unsupported syntax" errors. But it works on Firefox!
  • Closure Compiler inlined all my strings, which made my code size bigger. Why did it do that?
  • JSC_VAR_MULTIPLY_DECLARED_ERROR occur using the standalone compiler jar but not with the web service
  • My code broke when using advanced optimizations! How do I figure out what's wrong?
  • Some of my properties are getting renamed, but some aren't. Why?
  • When using type-checking, sometimes Closure Compiler doesn't warn me about missing properties. Why not?
  • I got a "partial alias created for namespace" error. What do I do?
  • The short answer
  • What's the deal with using the fully qualified name?
  • What is this happening with yield and await, then?
  • Using Closure Compiler
  • What version of Java is required?
  • What are the recommended Java VM command-line options?
  • How do I use Advanced Optimizations?
  • I want to use Advanced Optimizations, but { jQuery, YUI, Underscore, Prototype, JS Library Foo } does not work with them. What do I do?
  • Do I need to write type annotations to take advantage of Advanced Optimizations?
  • When using Advanced Optimizations, Closure Compiler adds new variables to the global scope. How do I make sure my variables don't collide with other scripts on the page?
  • How do I call Closure Compiler from the Java API?
  • How do I write an externs file?
  • How do I add closure-compiler functionality to my project?
  • What version of Closure Compiler should I use?
  • Source Maps and sourceMappingURL
  • Contributions
  • How do I submit a patch?
  • How do I submit a bug report?
  • How do I submit a feature request for a new type of optimization?
  • Design of Closure Compiler
  • How do I find out more about how Closure Compiler works?
  • Is there a specification for the JSDoc type language?
  • Can you add alternative syntax X to your JSDoc type language?
  • My question isn't covered on this list!