Anyone know why __END__ and DATA don't work in Rails?

rubyonrails-talk
1

When writing Ruby you have the option to end the file early with __END__. Anything after the __END__ is assigned to a constant called DATA which is available within the file.

I recently tried using this in Rails and it didn't work. Instead I get an uninitialized constant exception. Anyone know why?

Has it been disabled in Rails?

thanks

Gavin

2

The DATA constant is only created for the running script. Thus, require'd files do not get the DATA constant.

see the following:

xeno@amrita:~ $ cat data.rb puts DATA.read __END__ helloooooo xeno@amrita:~ $ cat d2.rb require 'data' xeno@amrita:~ $ ruby data.rb helloooooo xeno@amrita:~ $ ruby d2.rb /home/xeno/data.rb:1:in `<top (required)>': uninitialized constant DATA (NameError)         from d2.rb:1:in `require'         from d2.rb:1:in `<main>' xeno@amrita:~ $

3

That makes sense!

Thanks for that!