From: MonkeeSage <MonkeeSage@...>
Date: 2006-09-19T09:16:21+09:00
Subject: Re: Why not a Ruby 1.8 to 2.x Code Convertor?

Since 1.8 (and 1.9, and 1.6 even) can be installed at the same time as
2.0, a better option, imo, would be to add a built-in keyword or
Kernel-method whereby you can specify what version of the interpreter a
given script is meant for, and issue a warning if that is not the
version being used to execute the script. Something like:

use 1.8
# ... the rest of the script

A simple implementation could be:

module Kernel
  def use(version)
    unless RUBY_VERSION.include?(version.to_s)
      warn "Warning: Wrong ruby version:\n" \
           "Expected #{version}, but got #{RUBY_VERSION}"
    end
  end
end

Many programming platforms go through major, incompatible changes every
now and then (e.g., gcc3 vs. gcc4), but the world hasn't imploded yet
with productivity grinding to a halt; people either use the legacy
version with their legacy code, or else update their code and use the
new version.

Regards,
Jordan