[#329967] Ruby beginner Problem — Zayd Connor <devrubygem@...>

I get the following error message when running the code below:

18 messages 2009/03/01
[#329972] Re: Ruby beginner Problem — lasitha <lasitha.ranatunga@...> 2009/03/01

On Sun, Mar 1, 2009 at 10:46 AM, Zayd Connor <devrubygem@gmail.com> wrote:

[#329973] Re: Ruby beginner Problem — Zayd Abdullah <devrubygem@...> 2009/03/01

Thanks Lasitha that worked perfect. I'm slowly getting more comfortable with

[#329975] Re: Ruby beginner Problem — Justin Collins <justincollins@...> 2009/03/01

Zayd Abdullah wrote:

[#330022] Delegating class methods — abc <arcadiorubiogarcia@...>

Hi all,

17 messages 2009/03/01

[#330038] Rub 1.9: "inline rescue" doesn't work? — Iñaki Baz Castillo <ibc@...>

Hi, is there any explanation for the folowing big difference between the same

11 messages 2009/03/01

[#330067] passing a method as a paramter — Sarah Allen <sarah@...>

I'm probably missing some basic Ruby syntax, but I'm relatively new to

13 messages 2009/03/02

[#330097] Compiling a Ruby app — Sharagoz -- <blashyrkh1@...>

Hi

22 messages 2009/03/02
[#330193] Re: Compiling a Ruby app — David Masover <ninja@...> 2009/03/03

Sharagoz -- wrote:

[#330209] expanding environment variable — Daniel Schoch <trash@...>

Hi,

13 messages 2009/03/03
[#330212] Re: expanding environment variable — Dominik Honnef <dominikho@...> 2009/03/03

On [Tue, 03.03.2009 23:28], Daniel Schoch wrote:

[#330246] fixnum problem plz help — Guy Dols <guy_dols@...>

hy

14 messages 2009/03/03

[#330287] Any solutions to Ruby's inconsistencies? — "C. Dagnon" <c-soc-rubyforum@...>

Ruby has definite positives over Java and even other scripting

29 messages 2009/03/04
[#330292] Re: Any solutions to Ruby's inconsistencies? — Yossef Mendelssohn <ymendel@...> 2009/03/04

On Mar 4, 10:02m, "C. Dagnon" <c-soc-rubyfo...@dagnon.net> wrote:

[#330322] Re: Any solutions to Ruby's inconsistencies? — "C. Dagnon" <c-soc-rubyforum@...> 2009/03/04

Yossef Mendelssohn wrote:

[#330388] Re: Any solutions to Ruby's inconsistencies? — Yossef Mendelssohn <ymendel@...> 2009/03/05

On Mar 4, 3:32m, "C. Dagnon" <c-soc-rubyfo...@dagnon.net> wrote:

[#330401] Re: Any solutions to Ruby's inconsistencies? — "C. Dagnon" <c-soc-rubyforum@...> 2009/03/05

Yossef Mendelssohn wrote:

[#330363] Ruby -Question about Framewroks — jazzez ravi <jazzezravi@...>

Hi All,

12 messages 2009/03/05

[#330383] add a new line after, w/txtfile thats comma delimited — Mmcolli00 Mom <mmc_collins@...>

How do you add a new line after you have split a text file with

16 messages 2009/03/05

[#330387] Ruby - Imperative Language Features? — Mike Stephens <rubfor@...>

The Wikipedia entry for Ruby says:

12 messages 2009/03/05

[#330601] how to un-ragged a 2D array? — Phlip <phlip2005@...>

Rubies:

12 messages 2009/03/07

[#330630] Can I access or find a object from it's instance variable? — Aki Wakabayashi <zzyzx2001@...>

Hello.

14 messages 2009/03/08

[#330638] OO style tutorials? — Paul Archer <paul@...>

I'm pretty new to Ruby, and while I've read (and mostly get) several books

20 messages 2009/03/08

[#330665] What are the 5 most innovative ruby projects/libraries? — Camille Roux <roux.camille@...>

Hi,

27 messages 2009/03/08

[#330701] Ruby OpenGL Gears example that uses shiny and velvet GLSL shaders — Michael Brooks <michael.brooks@...>

Hello:

11 messages 2009/03/09
[#330722] Re: Ruby OpenGL Gears example that uses shiny and velvet GLSL shaders — Matthias Reitinger <reitinge@...> 2009/03/09

Michael Brooks wrote:

[#330718] MacRuby 0.4 — Laurent Sansonetti <laurent.sansonetti@...>

Hi,

17 messages 2009/03/09

[#330954] How Many hours in A day — Zayd Connor <devrubygem@...>

I have a very simple ? How many hours in a day should someone who is new

17 messages 2009/03/11

[#330990] How to read a charecters from and image? — rails and rails only <mjayakumar2k6@...>

16 messages 2009/03/12
[#330993] Re: How to read a charecters from and image? — pjb@... (Pascal J. Bourguignon) 2009/03/12

rails and rails only <mjayakumar2k6@yahoo.com> writes:

[#330994] Re: How to read a charecters from and image? — Redd Vinylene <reddvinylene@...> 2009/03/12

Stop that! He's probably looking to crack CAPTCHAs.

[#331216] does IO.read block? — Michael Malone <michael.malone@...>

Hi All,

16 messages 2009/03/15
[#331218] Re: does IO.read block? — Robert Klemme <shortcutter@...> 2009/03/15

On 15.03.2009 23:02, Michael Malone wrote:

[#331307] Trying to install Fox, FXRuby, and IFMapper on Mac OS X — kpkilburn@...

I can't seem to find a specific answer on this...

12 messages 2009/03/16

[#331326] Dynamically extending modules once they have been included — pete@...373.net

It doesn't seem possible to dynamically extend modules once they have

14 messages 2009/03/17

[#331371] free RAM problem — Edouard Dantes <edrd.dantes@...>

Hi,

14 messages 2009/03/17

[#331411] hpricot 0.7 — _why <why@...>

Please enjoy a succulent, new Hpricot. A bit faster, some Ruby 1.9

25 messages 2009/03/17

[#331476] Complex sort of matrix possible, e.g. like Excel? — RichardOnRails <RichardDummyMailbox58407@...>

Hi,

18 messages 2009/03/18

[#331478] REXML get specific element — Pierre Pat <theyojimbo@...>

All,

15 messages 2009/03/18

[#331568] Modulo ? — Zayd Connor <devrubygem@...>

Maybe i need to get some sleep, but can someone explain how modulos

16 messages 2009/03/19

[#331628] Passing a named function instead of a code block? — Paul Jungwirth <once@9stmaryrd.com>

Hello,

13 messages 2009/03/20
[#331630] Re: Passing a named function instead of a code block? — Matthias Reitinger <reitinge@...> 2009/03/20

Paul Jungwirth wrote:

[#331760] Ruby GUI Libs — ntwrkd <ntwrkd@...>

Is there a nicer GUI framework for Ruby other than RubyGoo?

12 messages 2009/03/21

[#331793] Newbie needs help with first project — Daniel Dale <dochappy@...>

I was told about Ruby several weeks ago and started my journey lol. I've

15 messages 2009/03/22
[#331796] Re: Newbie needs help with first project — Stefan Codrescu <fixxie.wits@...> 2009/03/22

On Sun, Mar 22, 2009 at 9:32 AM, Daniel Dale <dochappy@gmail.com> wrote:

[#331803] convert PNG to hex — jeljer te Wies <jeljer@...>

Hey people! ..

20 messages 2009/03/22

[#331899] Test::Unit - same test, different "args" — "Luke St.Clair" <secureboot@...>

I need to run the same unit test case more than 10 times (around 150

14 messages 2009/03/23

[#331924] Mimic AES_ENCRYPT and AES_DECRYPT functions in Ruby — Felipe Coury <felipe.coury@...>

Hello there!

20 messages 2009/03/24
[#331931] Re: Mimic AES_ENCRYPT and AES_DECRYPT functions in Ruby — gcristelli <giovanni.cristelli@...> 2009/03/24

On 24 Mar, 04:21, Felipe Coury <felipe.co...@gmail.com> wrote:

[#331938] Re: Mimic AES_ENCRYPT and AES_DECRYPT functions in Ruby — Felipe Coury <felipe.coury@...> 2009/03/24

Giovanni / Rob,

[#331940] Re: Mimic AES_ENCRYPT and AES_DECRYPT functions in Ruby — Felipe Coury <felipe.coury@...> 2009/03/24

Some more discoveries...

[#331941] Re: Mimic AES_ENCRYPT and AES_DECRYPT functions in Ruby — Felipe Coury <felipe.coury@...> 2009/03/24

Just as a FYI, it works!!!

[#331948] Re: Mimic AES_ENCRYPT and AES_DECRYPT functions in Ruby — Rob Biedenharn <Rob@...> 2009/03/24

On Mar 24, 2009, at 2:35 AM, Felipe Coury wrote:

[#365126] Re: Mimic AES_ENCRYPT and AES_DECRYPT functions in Ruby — Joshua Mckinney <joshmckin@...> 2010/07/01

Having no luck with this. Getting the following error when generating

[#331930] tagz-5.0.0 — "ara.t.howard" <ara.t.howard@...>

44 messages 2009/03/24
[#332078] Re: [ANN] tagz-5.0.0 — "Andrew S. Townley" <ast@...> 2009/03/25

Hi Ara,

[#332095] Re: [ANN] tagz-5.0.0 — "ara.t.howard" <ara.t.howard@...> 2009/03/25

[#332141] Re: [ANN] tagz-5.0.0 — "Andrew S. Townley" <ast@...> 2009/03/25

On Wed, 2009-03-25 at 23:23 +0900, ara.t.howard wrote:

[#332160] Re: [ANN] tagz-5.0.0 — "ara.t.howard" <ara.t.howard@...> 2009/03/26

[#331971] : HOWTO start irb on a different object — Jeremy Henty <onepoint@...>

I wanted to have irb start its session on an object other than the

10 messages 2009/03/24

[#332023] ruby and 2D graphics — Philip Müller <me@...>

Hi everybody,

22 messages 2009/03/24
[#332029] Re: ruby and 2D graphics — Philip Müller <me@...> 2009/03/24

On Tue, 24 Mar 2009 21:08:34 +0100, Peter Zotov <whitequark@whitequark.ru>

[#332112] Parsing xml — Arun Kumar <arunkumar@...>

Hi,

24 messages 2009/03/25
[#332115] Re: Parsing xml — "Peter Zotov" <whitequark@...> 2009/03/25

Quoting "Arun Kumar" <arunkumar@innovaturelabs.com>:

[#332116] Re: Parsing xml — Arun Kumar <arunkumar@...> 2009/03/25

Peter Zotov wrote:

[#332118] Re: Parsing xml — "Peter Zotov" <whitequark@...> 2009/03/25

Quoting "Arun Kumar" <arunkumar@innovaturelabs.com>:

[#332206] Update latest Ruby Version 1.9 on Mac OSX — Thomas Khaipi <sayakyi@...>

Dear All,

14 messages 2009/03/26

[#332357] testy.rb - ruby testing that's mad at the world — "ara.t.howard" <ara.t.howard@...>

55 messages 2009/03/28
[#332418] Re: testy.rb - ruby testing that's mad at the world — Brian Candler <b.candler@...> 2009/03/29

Ara Howard wrote:

[#332405] Ruby 1.9, OS X, command line: negative string size (ArgumentError) — Bartlomiej Owczarek <bartlomiej@...>

Hello,

13 messages 2009/03/29

[#332474] Symbols garbage collector in Ruby1.9, fixed? — Iñaki Baz Castillo <ibc@...>

Hi, in Ruby 1.8 there is an issue when adding more and more Symbols

27 messages 2009/03/30

[#332520] When to use instance variables @ — Steve Dogers <stevedogers@...>

Hi, I have a couple questions about instance variables in Ruby.

20 messages 2009/03/30

[#332547] Localmemcache-0.2.0: The beauty of memcached. For local data. Blazingly fast. — "Sven C. Koehler" <schween@...>

Hi,

13 messages 2009/03/30

[#332624] Move over, Phusion, here comes the *real* Enterprise Edition! — Jg W Mittag <JoergWMittag+Usenet@...>

Hi!

20 messages 2009/03/31

Re: Problem With eval and each_index

From: Christopher Dicely <cmdicely@...>
Date: 2009-03-15 17:12:28 UTC
List: ruby-talk #331193
On Sat, Mar 14, 2009 at 4:47 PM, Michael W. Ryder
<_mwryder@worldnet.att.net> wrote:
> matt neuburg wrote:
>>
>> Michael W. Ryder <_mwryder@worldnet.att.net> wrote:
>>
>>> I am trying to set a group of variables to values stored in a tab
>>> delimited string.  I have no problem splitting the string into an array,
>>> call it e, or in putting the variable names in a second array, call it
>>> v.  The problem arises when I try to merge the two together.  If I enter:
>>> irb(main):073:0> p v
>>> ["name", "street", "city", "state", "zip", "*", "telephone"]
>>> => nil
>>> irb(main):074:0> p e
>>> ["John Doe", "123 Main St", "Anywhere", "US", "01234-5678", "ab123",
>>> "1234567890"]
>>> => nil
>>> irb(main):075:0> eval "#{v[0]} = e[0]"
>>> => "John Doe"
>>> irb(main):076:0> p name
>>> "John Doe"
>>> => nil
>>>
>>> it works as I want.  But when I try:
>>> irb(main):077:0> v.each_index {|i| eval "#{v[i]} = e[0]"}
>>> => ["name", "street", "city", "state", "zip", "*", "telephone"]
>>>
>>> and then enter: puts zip
>>> it returns with a NameError saying that the variable was undefined.
>>
>> Inside a block, local variables are local to the block. So, you're
>> creating all those local variables and then the block ends and they are
>> all thrown away.
>>
>
> I can see that if I create the variable before running the method the
> variable is set even after the method ends.  Which of course brings up the
> question of why is the change visible outside of the block?

Ruby blocks are closures, and they therefore capture the environment
where they are created. So if a local variable exists in that
environment when the block is created, the block has access to it, and
changes will affect the externally-created local variable. But new
local variables introduced in the block are local to the block. In
essence, the environment of the block is subordinate to the
environment in which it is created.

>
>> Why do you need variables called "name" (etc.) anyway? Why not use a
>> hash, so that h["name"] contains the name ("John Doe"), h["street"]
>> contains the street, and so on? So:
>>
>
> I have been programming in Business Basic for over 20 years and am used to
> reading a file with a statement like:
>  Read(1,Key="1234")Name$,Street$,City$,State$,Zip$,*,Telephone$
> and then using those variables.

Assuming you have a "keyed_read" method defined properly, you can easily do:

name, street, city, state, zip, _, telephone =
data_file.keyed_read(:key=>"1234")

But the thing that is harder is dynamically assigning variable names
based on a array provided. Using hashes or structs are the more
idiomatic Ruby ways of doing something similar to that. Its possible
to do something very close to what you were attempting with instance
variables using Object#instance_variable_set.

irb(main):036:0> v.zip(e).each { |var, val|
irb(main):037:1* begin
irb(main):038:2* self.instance_variable_set(("@"+var).to_sym,val)
irb(main):039:2> rescue
irb(main):040:2> end
irb(main):041:1> }
=> [["name", "John Doe"], ["street", "123 Main St"], ["city",
"Anywhere"], ["state", "US"], ["zip", "01234-5678"], ["*", "ab123"],
["telephone", "1234567890"]]
irb(main):042:0> @name
=> "John Doe"

So if you want to do it that way, you can. (Note, I'm assuming that
the '*' is a special symbol for a value you don't want to store, if
not, you'll have to add some logic to map that to a valid instance
variable name.)

In This Thread