From: brabuhr@...
Date: 2009-07-26T08:48:29+09:00
Subject: Re: Please debug this program

On Sat, Jul 25, 2009 at 7:24 PM, Brian Candler<b.candler@pobox.com> wrote:
> I'm surprised it even ran at all:
>
> def factorial(x)
>  if (x==0) then
>    return (1)
>    end
>    else
>      ... something else
>
> This doesn't make sense syntactically - an 'else' without an 'if'.

An 'else' can live inside a method or a begin...end:

> ruby y
y:6: warning: else without rescue is useless
FOO
ELSE
FOO
y:3:in `foo': FOO (RuntimeError)
        from y:9

> cat y
def foo(n)
  puts "FOO"
  raise "FOO" if n
rescue
  puts "RESCUE"
else
  puts "ELSE"
end

foo(false)
foo(true)
> ruby y
FOO
ELSE
FOO
RESCUE


http://rubycentral.com/pickaxe/tut_exceptions.html
"The else clause is a similar, although less useful, construct. If
present, it goes after the rescue clauses and before any ensure. The
body of an else clause is executed only if no exceptions are raised by
the main body of code."