How to run a Frege class file

Question

How to run a Frege class file

halloleo opened this issue 2 years ago · 2 comments

Probably a very silly question, but how can I run a class file Frege has generated?

Here's what I've done:

I wrote Frege source file hallo.fr:

greet name = "Hallo " ++ name

main = do
  println (greet "Duda")

I compiled it with:

java -jar frege3.25.84.jar hallo.fr

I got a Main.class file which I try to run via:

java Main

However I get the error

Error: A JNI error has occurred, please check your installation and try again
Exception in thread "main" java.lang.NoClassDefFoundError: frege/prelude/PreludeText$CShow

The Frege jar is in the current directory, so I tried as well

java -cp "." Main

but I got the same error. Do I need another jar to run the class file?

Answer 1 · 2022-09-13T07:55:17.000Z

One needs to have the Frege jar in the classpath, please read the how to get started document. halloleo ***@***.***> schrieb am Mo., 12. Sept. 2022, 09:08:

…

Probably a very silly question, but how can I run a class file Frege has generated? Here's what I've done: 1. I wrote Frege source file hallo.fr: greet name = "Hallo " ++ name main = do println (greet "Duda") 1. I compiled it with: java -jar frege3.25.84.jar hallo.fr 1. I got a Main.class file which I try to run via: java Main However I get the error Error: A JNI error has occurred, please check your installation and try again Exception in thread "main" java.lang.NoClassDefFoundError: frege/prelude/PreludeText$CShow The Frege jar is in the current directory, so I tried as well java -cp "." Main but I got the same error. Do I need another jar to *run* the class file? — Reply to this email directly, view it on GitHub <#395>, or unsubscribe <https://github.com/notifications/unsubscribe-auth/AAF725XICP4JWCHVATZ6I33V53JGPANCNFSM6AAAAAAQKFLKFM> . You are receiving this because you are subscribed to this thread.Message ID: ***@***.***>

Answer 2 · 2022-09-14T00:47:54.000Z

Thanks for getting back to me!

I forgot that the JAR itself needs to be in the CLASSPATH property, not only the directory containing the JAR. -- This is somewhat similar to Haskell (where each module needs to be listed in package.conf.d).