From: Michiel de Mare <merloen@...>
Date: 2007-10-16T00:40:03+09:00
Subject: using String#slice with a symbol argument.

Currently, ruby 1.8.6. has the following behavior:

'ruby'[:en] #=> nil

 The reason is that the symbol is converted to an integer using
to_int. But this is never useful, and can be a source of obscure bugs
when your variable contains a string instead of an hash.

Wouldn't raising an exception be more appropriate?