"Developing Games With Ruby" Stuck at creating prototype tank game



I don’t know why , i followed the code sample and it didn’t work, it seems like it is outdated?
Is there anyone who can fix this?


You may want to give us a bit more context. What guide did you follow? What are you stuck on?


I currently following “Developing Games With Ruby” https://leanpub.com/developing-games-with-ruby/read

Im stuck at “Prototyping The Game” chapter where i tried the program which the compilation failed.