:s.respond_to?(:dup) && :s.dup raises

fbeausoleil · April 5, 2007, 7:42pm

Hi all !

Symbol lies about it’s ability to respond_to? to #dup:

irb(main):001:0> :s.respond_to?(:dup)
=> true
irb(main):002:0> :s.dup
TypeError: can’t dup Symbol
from (irb):2:in `dup’
from (irb):2

Fixnum does the same thing. You might argue that the object can
respond to :dup, except it’s simply illegal to respond to it.

Anyway, my feeling is that Symbol and Fixnum (probably Numeric) should
not respond_to?(:dup).

Thanks !

fbeausoleil · April 5, 2007, 7:55pm

FranÃ§ois Beausoleil wrote:

Anyway, my feeling is that Symbol and Fixnum (probably Numeric) should
not respond_to?(:dup).

Here’s a 76-post thread on this very subject, from about six, seven
weeks ago.