[#796] Re: value of assignment (Re: Order of the value of an expression changed? (PR#579)) — Sean Chittenden <sean@...>

> sean@chittenden.org wrote:

33 messages 2003/02/06
[#798] Re: value of assignment (Re: Order of the value of an expression changed? (PR#579)) — matz@... (Yukihiro Matsumoto) 2003/02/06

Hi,

[#826] Re: value of assignment (Re: Order of the value of an expression changed? (PR#579)) — Sean Chittenden <sean@...> 2003/02/10

> |I have read the thread and I think this is a pretty bad change. I

[#827] Re: value of assignment (Re: Order of the value of an expression changed? (PR#579)) — nobu.nokada@... 2003/02/10

Hi,

[#828] Re: value of assignment (Re: Order of the value of an expression changed? (PR#579)) — Sean Chittenden <sean@...> 2003/02/11

> > #BEGIN test.rb

[#829] Re: value of assignment (Re: Order of the value of an expression changed? (PR#579)) — matz@... (Yukihiro Matsumoto) 2003/02/11

Hi,

[#830] Re: value of assignment (Re: Order of the value of an expression changed? (PR#579)) — Sean Chittenden <sean@...> 2003/02/11

> |What was wrong with having the receiver set the return value though?

[#834] Re: value of assignment (Re: Order of the value of an expression changed? (PR#579)) — Matt Armstrong <matt@...> 2003/02/11

Sean Chittenden <sean@chittenden.org> writes:

[#835] Re: value of assignment (Re: Order of the value of an expression changed? (PR#579)) — Sean Chittenden <sean@...> 2003/02/11

> > f = Foo.new()

[#801] class of $1, $2 in 1.8.0 — dblack@...

Hi --

31 messages 2003/02/07
[#802] Re: class of $1, $2 in 1.8.0 — nobu.nokada@... 2003/02/07

Hi,

[#803] Re: class of $1, $2 in 1.8.0 — dblack@... 2003/02/07

Hi --

[#804] Re: class of $1, $2 in 1.8.0 — matz@... (Yukihiro Matsumoto) 2003/02/07

Hi,

[#805] Re: class of $1, $2 in 1.8.0 — dblack@... 2003/02/07

Hi --

[#806] Re: class of $1, $2 in 1.8.0 — "J.Herre" <jlst@...> 2003/02/07

[#807] Re: class of $1, $2 in 1.8.0 — Matt Armstrong <matt@...> 2003/02/07

J.Herre <jlst@gettysgroup.com> writes:

[#808] Re: class of $1, $2 in 1.8.0 — dblack@... 2003/02/07

Hi --

[#809] Re: class of $1, $2 in 1.8.0 — Ryan Pavlik <rpav@...> 2003/02/07

On Sat, 8 Feb 2003 06:52:17 +0900

[#810] Re: class of $1, $2 in 1.8.0 — dblack@... 2003/02/07

Hi --

[#889] Bob Jenkins' hashing implementation in Ruby — Mauricio Fern疣dez <batsman.geo@...>

16 messages 2003/02/28
[#892] Re: Bob Jenkins' hashing implementation in Ruby — ts <decoux@...> 2003/03/01

>>>>> "M" == Mauricio Fern疣dez <Mauricio> writes:

[#893] Re: Bob Jenkins' hashing implementation in Ruby — Mauricio Fern疣dez <batsman.geo@...> 2003/03/01

On Sat, Mar 01, 2003 at 08:42:40PM +0900, ts wrote:

Re: class of $1, $2 in 1.8.0

From: dblack@...
Date: 2003-02-08 01:36:10 UTC
List: ruby-core #814
Hi --

On Sat, 8 Feb 2003, J.Herre wrote:

> It make sense that String#scan, String#slice, String#dup all return
> various parts of
> the given string.  Would it make sense for SpecializeString#dup to
> return a
> String?  Shouldn't #slice, #split and #scan do the same thing?
>
> Why not assume that a substring of a string is the same kind of string?
>   What's
> the advantage of the old behavior?

Even if the new class is specialized, substrings of it may not be
similarly specialized -- in which case, it's misleading to have them
be instances of the new class.  For example:

  class Name < String
    def initial
      scan(/[A-Z]/)[0]
    end
  end

  n = Name.new("David")
  i = n.initial          # String in 1.6.8, Name in 1.8.0

Here, it doesn't seem logical (to me) for an initial to be a Name
object.  (Yes, I could have done self[0].chr, but I need to illustrate
this :-)

I don't think having the initial be a String is a demotion in a case
like this.  It's just coincidence that the superclass of self's class
happens to be the same as the class of objects returned by #scan.  If
you had:

  class Title < String
    def separator
      " "
    end
  end

you wouldn't expect " " to be a Title object.  Similarly (I would
argue), the substring "D" is just a string, even though it happens to
come from an operation on a Name object.


David

-- 
David Alan Black
home: dblack@candle.superlink.net
work: blackdav@shu.edu
Web:  http://pirate.shu.edu/~blackdav


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