Command line compilation of Hello World in Eiffel (Unknown root class error)

Question

I'm trying to build a hello world program in Eiffel, and this is how I tried. I use Mac OS X 10.10.

I installed the Eiffel programming language with brew install eiffelstudio. Everything works fine without an issue. I have all the tools in /usr/local/Cellar/eiffelstudio/14.05
I came up with an example code from this site: https://dev.eiffel.com/Compiling_Hello_World

This is the code.

class
    ROOT_CLASS
create
    make
feature -- Initialization 
    make
        -- Creation procedure.
        do
            io.put_string ("Hello World!")
        end   
end

I'm trying to build this code into a binary that can be executed.

I tried ec hello.e to get this error message.

Configuration error: Unknown root class.
What to do: Make sure that the name given in the Ace for the root
  class corresponds to a class of the universe. (If more than
  one, specify the cluster, see example in ETL D.2, page 514.)

What might be wrong?

score 2 · Accepted Answer · answered Mar 24 '15 at 14:13

2

The name of the file and the name of the class should be the same, so the error should disappear if you either rename the file to root_class.e or change the class name to read HELLO.

answered Mar 24 '15 at 14:13

Alexander Kogtenkov

5,770
1
27
35

I got root_class binary and root_class.ecf, then how to execute the binary? Thanks. – prosseek Mar 24 '15 at 15:59
@prosseek, the executable is located in `EIFGENs/root_class/W_code` with the name `root_class`. Normally you use a command-line shell to run it. – Alexander Kogtenkov Mar 24 '15 at 16:20

Command line compilation of Hello World in Eiffel (Unknown root class error)

1 Answers1