From: ts <decoux@...>
Date: 2001-09-19T01:00:52+09:00
Subject: [ruby-talk:21336] Re: if before or if after?

>>>>> "P" == Paul Brannan <pbrannan@atdesk.com> writes:

P>   x = '' if not defined?(x)

 At compile time, `x' is resolved as a local variable (ruby has seen an
 assignement). A local variable is always defined.

P>   if not defined?(x) then x = '' end
     p x

 At compile time the first `x' is resolved as a method call (this is the
first time than ruby see it). Because there is no method #x, defined?(x)
return nil.

 The second occurence (x = '') is resolved as an local variable.

 The third occurence (p x) is resolved as an local variable because ruby
 has seen the x = ''

P>   x = '' if not defined?(x)
P>   if not defined?(x) then x = '' end
P>   p x

 This is always the local variable `x' which is referenced.


Guy Decoux