When is nil not false?

What about: def initialize(source=nil)   source ? xchg_source(source) : xchg_source end

Or if you prefer longer notation def initialize(source=nil)   if source     xchg_source(source)   else     xchg_source end

Or like in your example: def initialize(source=nil)   return xchg_source unless source   xchg_source(source) end