From: rcoder <rcoder@...>
Date: 2005-07-20T06:46:10+09:00
Subject: Re: IRB reset?

This isn't specific to IRb -- any time you reload code which defines
constants, (variables with names that begin with a capital letter, such
as 'MY_VARIABLE' or 'MyConstant') the Ruby runtime will throw a warning
about the constant being redefined.

You can see this behavior in its simplest form with code like the
following:

--- begin 'const_warn_demo.rb' ---

# set a constant
FOO = 'bar'

# do something...

# now, set the constant again
FOO = 'baz'

--- end ---

Constants are designed to be read-only values, so a warning when
they're re-assigned is appropriate. 

-Lennon