Does `@file:JvmSynthetic` still work? I can still ...

# multiplatform

[Edoardo Luppi]

Does @file:JvmSynthetic still work?
I can still access both the generated class and its methods in a Java project.

[mbonnin]

I usually put a - in the filename: @file:JvmName("-foo")

[mbonnin]

I never really questioned why but I guess this might be because @file:JvmSynthetic is not working

[Edoardo Luppi]

Thanks Martin, I do remember seeing the - prefix in Apollo, and I was really wondering why you were using that too

[Edoardo Luppi]

Was the - character choice random, or was it the only one to have the correct result?

[mbonnin]

It was stolen from okio 😄

[Edoardo Luppi]

Ah 😂 Well, I'll steal from Apollo then

[mbonnin]

OSS is sharing 🙂

[mbonnin]

I believe other chars could work too. Anything that is invalid in a Java class name

[Edoardo Luppi]

Answer from the Java specification regarding which char can be used as the first one for a class name:

The "Java letters" include uppercase and lowercase ASCII Latin letters A-Z (\u0041-\u005a), and a-z (\u0061-\u007a), and, for historical reasons, the ASCII underscore (_, or \u005f) and dollar sign ($, or \u0024). The $ character should be used only in mechanically generated source code or, rarely, to access pre-existing names on legacy systems.

[Edoardo Luppi]

The $ character should be used only in mechanically generated source code

Seems we could even go with $

[mbonnin]

Curious if we can do @file:JvmName("🙃")

[jw]

A dollar sign is still usable from Java. You can even define classes with an explicit dollar sign.

[jw]

The specification you want to look at is the class specification, not the Java specification. The point is to use a character which is valid in the class but not in Java.

[Edoardo Luppi]

Yeah you're right, although that would maybe follow a "convention" to identify generated stuff

[Edoardo Luppi]

The point is to use a character which is valid in the class but not in Java.

Noted, thanks

[CLOVIS]

although that would maybe follow a "convention" to identify generated stuff

well, "anything that isn't a legal identifier in Java" has to be generated stuff already