From: Hugh Sasse Staff Elec Eng <hgs@...>
Date: 2002-07-10T19:11:41+09:00
Subject: Re: Case expressions and LHS of assignment....

On Wed, 10 Jul 2002, Yukihiro Matsumoto wrote:

> Hi,
>
> In message "Case expressions and LHS of assignment...."
>     on 02/07/10, Hugh Sasse Staff Elec Eng <hgs@dmu.ac.uk> writes:
>
> |While trying to avoid Repetition in my code I tried to rewrite a case
> |statement, thinking how they can be used on the right hand side of an
> |assignment, so I tried the left hand side.  It basically came down to
> |this:
>
> Unlike Perl (nor C++), the evaluated result of case statement is the
> "value", not the "reference".  And I feel this is a good thing.  Why not

A good thing because it would lead to tangled code, "giving too much
rope to for the programmer to hang themselves" etc, or some other
reason?
>
>    def assign(x,y)
>       case x
>       when 1
>           @a = y
>       when 2
>           @b = y
>       when 3
>           @c = y
>       end
>     end
>

That is what I did in the end (well, 'y' was a big expression, so I used
a temp var to hold it):
       t = long_boring_expression
       case x
       when :one
          @a = t
and so on.  I was just trying to optimise my code in the direction of
the Don't Repeat Yourself rule, and wondered how far I could push it.

> 							matz.
>
        Hugh