How "safe" is it? I'm thinking, for example, of Google's closure compiler and the advanced optimizations, which can break some things.
Or roughly, if it compiles without errors, is it safe to assume it won't introduce new bugs?
Or roughly, if it compiles without errors, is it safe to assume it won't introduce new bugs?
Having said that, it's quite safe, but won't be undetectable. Code using eval could detect injected identifiers, we don't currently aim at preserving function names, and the method bodies you get with toString() are altered. That should be roughly it.