[#405207] Does `self` and `scope(local)` operate parallels? — "Kumar R." <lists@...>

I am heavily confused with the topic when thinking `self` and `local

21 messages 2013/03/01
[#405211] Re: Does `self` and `scope(local)` operate parallels? — "Kumar R." <lists@...> 2013/03/01

Just to help experts out there I am clearing my statement once again

[#405242] Confusion in instance method calls of super class from subclass — "Kumar R." <lists@...>

I was just playing to see the instance method calls from the subclass

16 messages 2013/03/02
[#405252] Re: Confusion in instance method calls of super class from subclass — Hans Mackowiak <lists@...> 2013/03/03

YOU DID NOT READ WHAT I WAS WRITTEN:

[#405250] Extending Ruby. Little help or guidance if you are willing! — Cliff Rosson <cliff.rosson@...>

Hi Folk,

21 messages 2013/03/03
[#405393] Re: Extending Ruby. Little help or guidance if you are willing! — nannasin smith <lists@...> 2013/03/06

I've tried to do some reading but some of this is a bit over my head.

[#405549] Re: Extending Ruby. Little help or guidance if you are willing! — Cliff Rosson <cliff.rosson@...> 2013/03/10

Haven't been able to touch this in a week but I had a few minutes to look

[#405550] Re: Extending Ruby. Little help or guidance if you are willing! — Bartosz Dziewoński <matma.rex@...> 2013/03/10

On Sun, 10 Mar 2013 04:41:32 +0100, Cliff Rosson <cliff.rosson@gmail.com> wrote:

[#405600] Re: Extending Ruby. Little help or guidance if you are willing! — Cliff Rosson <cliff.rosson@...> 2013/03/11

Got ya. So it doesn't really matter if I convert things to ID and compare

[#405271] Confusion with Ruby's "case/when" block statement — "Kumar R." <lists@...>

Ruby uses `===` operator on the `case/when` type execution style.Now It

13 messages 2013/03/03

[#405310] How `next` works in ruby with `unless` ? — "Kumar R." <lists@...>

The `next` statement is used to skip a part of the loop and continue

25 messages 2013/03/04
[#405311] Re: How `next` works in ruby with `unless` ? — Joel Pearson <lists@...> 2013/03/04

Learn what semicolons do in Ruby.

[#405312] Re: How `next` works in ruby with `unless` ? — Matthew Kerwin <matthew@...> 2013/03/04

What Joel said.

[#405313] Re: How `next` works in ruby with `unless` ? — "Kumar R." <lists@...> 2013/03/04

Matthew Kerwin wrote in post #1100097:

[#405323] YourLanguageSucks — Kiswono Prayogo <kiswono@...>

Hi, i found this link.. https://wiki.theory.org/YourLanguageSucks

10 messages 2013/03/05

[#405376] When can one call themselves a “Rubyist”? — Rafal Chmiel <lists@...>

I was wondering what that term even meant. Is it something to do with

10 messages 2013/03/05

[#405400] Bignum-Fixnum-Numeric confusion — Pritam Dey <lists@...>

Hi,

13 messages 2013/03/06

[#405444] Question regarding automating some Outlook/IMAP and pdf parsing functions w/ ruby? — Ed Zimmerman <lists@...>

Hello,

20 messages 2013/03/07

[#405477] Compiling Ruby 2.0, problem with OpenSSL — "Piotr P." <lists@...>

Trying to compile Ruby 2.0 from source, having problem with it, getting

10 messages 2013/03/07

[#405495] RubyExcel class. Useful? — Joel Pearson <lists@...>

I've managed to create a (relatively) stable data-processing class which

32 messages 2013/03/08

[#405570] Confusion with block local variable declaration with block variable declaration within the pipe `|` — Love U Ruby <lists@...>

Why are we not allowed to create local variables or new object with

17 messages 2013/03/11

[#405597] Confusion with empty block printing — Love U Ruby <lists@...>

When I typed the below in my IRB:

18 messages 2013/03/11

[#405608] Access values for JSON.parse response — Nicole Villette <lists@...>

Hello, Does anyone know who to get the values from a nested hash in

17 messages 2013/03/11

[#405630] Confusion with some Module methods. — Love U Ruby <lists@...>

Can anyone help me to understand how the below module methods works?

16 messages 2013/03/12

[#405656] Confusion with Strings — Love U Ruby <lists@...>

From the book I read a line about string :

18 messages 2013/03/12

[#405762] Understanding Ruby Classes, Objects and Methods. — Kedar Mhaswade <lists@...>

Dear Rubyists,

12 messages 2013/03/13

[#405931] Finding one's way with 'super' in define_method/alias_emthod — Marcin Rzeźnicki <marcin.rzeznicki@...>

Hi all!

12 messages 2013/03/18
[#405935] Re: Finding one's way with 'super' in define_method/alias_emthod — Robert Klemme <shortcutter@...> 2013/03/18

On Mon, Mar 18, 2013 at 5:50 PM, Marcin Rze=C5=BAnicki

[#405936] Re: Finding one's way with 'super' in define_method/alias_emthod — "Marcin R." <lists@...> 2013/03/18

Robert Klemme wrote in post #1102151:

[#405942] Re: Finding one's way with 'super' in define_method/alias_emthod — Robert Klemme <shortcutter@...> 2013/03/18

On Mon, Mar 18, 2013 at 8:39 PM, Marcin R. <lists@ruby-forum.com> wrote:

[#405986] Ruby tainting on primitives — "Nicolas V." <lists@...>

Hi there,

18 messages 2013/03/20

[#405987] Why was the object_id for true and nil changed in ruby2.0? — Bharadwaj Srigiriraju <lists@...>

irb(main):001:0> true.object_id

11 messages 2013/03/20

[#406015] fixedpnt 0.0.1: Binary Fixed Point Calculations — Axel Friedrich <lists@...>

https://github.com/Axel2/fixedpnt.rb

12 messages 2013/03/20

[#406184] Nokogiri help parsing HTML — Paul Mena <lists@...>

I'm relatively new to Ruby (and therefore Nokogiri) and am trying to

18 messages 2013/03/26

[#406258] Translation Project — Jeremy Henderson <lists@...>

Hello all! This is my first post! I started learning Ruby about 3 weeks

22 messages 2013/03/28

[#406291] Hash with default — Harry Kakueki <list.push@...>

I would like to make a hash like h2 with the default described by h in one

12 messages 2013/03/29

[#406375] Ruby Gotchas presentation slides — Dave Aronson <rubytalk2dave@...>

I recently made available the slides for a presentation I did

13 messages 2013/03/30

[#406387] Private setters can be called by self, why not getters? — Josh Cheek <josh.cheek@...>

class Counter

9 messages 2013/03/31

Re: Ruby Gotchas presentation slides

From: Julian Leviston <julian@...>
Date: 2013-03-31 02:37:19 UTC
List: ruby-talk #406377

On 31/03/2013, at 10:55 AM, Dave Aronson <rubytalk2dave@davearonson.com> =
wrote:

> I recently made available the slides for a presentation I did
> recently, on Ruby Gotchas, at:
>=20
>  =
https://docs.google.com/presentation/d/1cqdp89_kolr4q1YAQaB-6i5GXip8MHyve8=
MvQ_1r6_s
>=20
> Other than the title, intro, and wrapup, there are 20 slides of
> gotchas, from beginner (string interpolation requires double quotes)
> to advanced (throw/catch vs. raise/rescue).  I'm thinking of turning
> it into a series of very brief screencasts.  Check it out, let me know
> what you think... and if you have any more gotchas you'd like me to
> cover.
>=20
> Thanks,
> Dave

This bothers me a little bit, because quite a few of your "gotchas" are =
about how ruby is ruby. For example, puts 'hi' if 0 is unexpected if =
you're a C programmer., but not if you're a smalltalker! But it's Ruby, =
not C or smalltalk!

Also, your slide 20 is about a closure, not a loop. This isn't a loop. =
An Enumerator/Iterator construction is not a loop! You can *think* of =
them as loops if you like, but an Enumerator is a class that can execute =
a closure/block many times, passing in different arguments sometimes. =
Point in case:

>> (1..4).map
=3D> #<Enumerator: 1..4:map>
>> e =3D _
=3D> #<Enumerator: 1..4:map>
>> e.next
=3D> 1
>> e.next
=3D> 2
>> e.next
=3D> 3

The Enumerator doesn't "close over" any local variables in the scope of =
its block... that would make no sense. If that were the case, it =
wouldn't be a closure anymore, it'd just be code in the main body. If =
you need variables that stick around, set the variable outside of the =
lexical scope of the closure, then it'll stick around.

Variables aren't "re-un-defined"! (*what* a verbal construction!), they =
merely fall out of scope when the closure finishes execution each time, =
so they don't exist anymore. If you're going to do some educating, it'd =
be good if you made sure the NEW information you are propagating is as =
correct as possible.

>> l =3D lambda{|val| val + 5}
=3D> #<Proc:0x007fb5bc9dfcf0@(irb):1 (lambda)>
>> (1..4).map(&l)
=3D> [6, 7, 8, 9]

It seems you know all this, but it'd be nice if you put it into your =
slides :)

Otherwise, nice work!

Julian


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