[#13775] Problems with racc rule definitions — Michael Neumann <neumann@...>

15 messages 2001/04/17
[#13795] Re: Problems with racc rule definitions — Minero Aoki <aamine@...> 2001/04/18

Hi,

[#13940] From Guido, with love... — Dave Thomas <Dave@...>

52 messages 2001/04/20

[#13953] regexp — James Ponder <james@...>

Hi, I'm new to ruby and am coming from a perl background - therefore I

19 messages 2001/04/21

[#14033] Distributed Ruby and heterogeneous networks — harryo@... (Harry Ohlsen)

I wrote my first small distributed application yesterday and it worked

15 messages 2001/04/22

[#14040] RCR: getClassFromString method — ptkwt@...1.aracnet.com (Phil Tomson)

It would be nice to have a function that returns a class type given a

20 messages 2001/04/22

[#14130] Re: Ruby mascot proposal — "Conrad Schneiker" <schneik@...>

Guy N. Hurst wrote:

21 messages 2001/04/24
[#14148] Re: Ruby mascot proposal — Stephen White <spwhite@...> 2001/04/24

On Tue, 24 Apr 2001, Conrad Schneiker wrote:

[#14188] Re: Ruby mascot proposal — matz@... (Yukihiro Matsumoto) 2001/04/25

Hi,

[#14193] Re: Ruby mascot proposal — "W. Kent Starr" <elderburn@...> 2001/04/25

On Tuesday 24 April 2001 23:02, Yukihiro Matsumoto wrote:

[#14138] Re: python on the smalltalk VM — Conrad Schneiker <schneik@...>

FYI: Thought this might be of interest to the JRuby and Ruby/GUI folks.

27 messages 2001/04/24
[#14153] Re: python on the smalltalk VM — Andrew Kuchling <akuchlin@...> 2001/04/24

Conrad Schneiker <schneik@austin.ibm.com> writes:

[#14154] array#flatten! question — Jim Freeze <jim@...> 2001/04/24

Hello.

[#14159] Can I insert into an array — Jim Freeze <jim@...> 2001/04/24

Ok, this may be a dumb question, but, is it possible to insert into an

[#14162] Re: Can I insert into an array — Dave Thomas <Dave@...> 2001/04/24

Jim Freeze <jim@freeze.org> writes:

[#14289] RCR: Array#insert — Shugo Maeda <shugo@...> 2001/04/27

At Wed, 25 Apr 2001 01:28:36 +0900,

[#14221] An or in an if. — Tim Pettman <tjp@...>

Hi there,

18 messages 2001/04/25

[#14267] Re: Ruby mascot proposal — "Conrad Schneiker" <schneik@...>

Danny van Bruggen,

16 messages 2001/04/26

[#14452] How to do it the Ruby-way 3 — Stefan Matthias Aust <sma@3plus4.de>

First a question: Why is

21 messages 2001/04/30

[ruby-talk:14129] Re: RCR: getClassFromString method

From: "rashworth" <rashworth@...>
Date: 2001-04-24 03:16:34 UTC
List: ruby-talk #14129
What is the Ruby code to produce a 3 row by 2 column matrix
of pixel elements, i.e. black and white?

Thank you.

Bob Ashworth

---------- Original Message ----------------------------------
From: "W. Kent Starr" <elderburn@mindspring.com>
Reply-To: ruby-talk@ruby-lang.org
Date: Tue, 24 Apr 2001 12:03:23 +0900

>On Monday 23 April 2001 18:18, Marko Schulz wrote:
>> On Tue, Apr 24, 2001 at 03:41:23AM +0900, Phil Tomson wrote:
>> > In article <988034673.396094.26164.nullmailer@ev.netlab.zetabits.com>,
>> >
>> > Yukihiro Matsumoto <matz@zetabits.com> wrote:
>> > > [ Should it be encouraged style of programming to retrieve a class
>> > >   by its name in a string? ]
>> >
>> > Well, perhaps it shouldn't be encouraged, I don't know.  I'm not
>> > necessarily an OO purist, I suppose.
>> >
>> > I know that I use this feature in a certain case where I have a class
>> > hierarchy like:
>> >
>> > class Tool
>> >   #methods to handle generic stuff common to PC and UNIX
>> > end
>> >
>> > class Tool_PC < Tool
>> >   #methods do PC specific stuff
>> > end
>> >
>> > class Tool_UNIX < Tool
>> >   #methods do UNIX related stuff
>> > end
>> >
>> > Let's say that early on in the script I figure out what platform I'm
>> > running on, say:
>> > $PLATFORM = "PC"  ($PLATFORM is global so I can instantiate
>> > Tool_"$PLATFORM" objects anywhere later on in the script)
>> >
>> > Then I can instantiate the correct class based on the value of PLATFORM
>> >
>> > There are probably other ways to do this, but getting the Class from a
>> > String seems pretty straitforward in this case - and it is how I've
>> > implemented this.
>> >
>> > So maybe it's not a good 'pure' thing to allow, but it does have its
>> > uses.
>>
>> I would use a factory-method for this:
>>
>>   class ToolFactory
>>
>>      def ToolFactory.getTool
>>        case $PLATFORM
>>          when "Unix" then Tool_Unix
>>          when "PC"   then Tool_PC
>>          else             nil
>>        end
>>      end
>>
>>   end
>>
>>
>> I would favor passing the platform as a parameter since I don't like
>> global variables.
>
>FYI Ruby provides this natively.
>
>ruby -e 'p RUBY_PLATFORM' -> "i586-linux" on my Redhat box.
>
>It will yield similar info on other platforms. The result can be parsed as in
>
>if RUBY_PLATFORM =~ /^(.*)linux$/
>
>etc
>
>Hope tis helps.
>
>Regards,
>
>Kent Starr
>elderburn@mindspring.com
>

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