From: Austin Ziegler <austin@...>
Date: 2004-02-05T01:58:30+09:00
Subject: Re: RCR draft for enhanced "case..when..else..end" syntax

On Wed, 4 Feb 2004 01:00:25 +0900, Gennady wrote:
> Guoliang Cao wrote:
> Do you know about this syntax currently available?

> a = "aaa"
> b = "bbb"
> case
>   when a == "aaa", b == "bbb"
>     puts "Lowercase detected"
>   when a == "AAA", b == "BBB"
>     puts "Uppercase detected"
>   else
>     puts "Detection failed"
> end

What you've written here will do alternatives checks. Thus, if you have:

a = "aaa"
b = "BBB"

then "Lowercase detected" will be printed. With "AAA" and "bbb", "Lowercase 
detected" will still be printed.

irb(main):001:0> def ct(a, b)
irb(main):002:1>   case
irb(main):003:2*     when a == "aaa", b == "bbb"
irb(main):004:2>       puts "Lowercase"
irb(main):005:2>     when a == "AAA", b == "BBB"
irb(main):006:2>       puts "Uppercase"
irb(main):007:2>     else
irb(main):008:2*       puts "Failed"
irb(main):009:2>   end
irb(main):010:1> end # => nil
irb(main):011:0> ct("aaa", "bbb") # Lowercase => nil
irb(main):012:0> ct("aaa", "BBB") # Lowercase => nil
irb(main):013:0> ct("AAA", "BBB") # Uppercase => nil
irb(main):014:0> ct("AAA", "bbb") # Lowercase => nil

-austin
--
austin ziegler    * austin@halostatue.ca * Toronto, ON, Canada
software designer * pragmatic programmer * 2004.02.04
                                         * 11.53.52