[#50466] [ruby-trunk - Bug #7492][Open] Segmentation fault at DL::TestDL#test_call_double on x64 Windows 8 — "phasis68 (Heesob Park)" <phasis@...>
23 messages
2012/12/02
[#59083] [ruby-trunk - Bug #7492] Segmentation fault at DL::TestDL#test_call_double on x64 Windows 8
— "phasis68 (Heesob Park)" <phasis@...>
2013/12/13
[#50483] [IMPORTANT] 2.0.0 release plan — Yusuke Endoh <mame@...>
ALL COMMITTERS SHOULD READ THIS MAIL! コミッタはこのメール読んで！
5 messages
2012/12/02
[#50561] [ruby-trunk - Bug #7513][Open] TracePoint#enable/disable should not cause error — "ko1 (Koichi Sasada)" <redmine@...>
7 messages
2012/12/05
[#50575] [ruby-trunk - Feature #7517][Open] Fixnum::MIN,MAX — "matz (Yukihiro Matsumoto)" <matz@...>
20 messages
2012/12/05
[#50593] [ruby-trunk - Feature #7517] Fixnum::MIN,MAX
— "shyouhei (Shyouhei Urabe)" <shyouhei@...>
2012/12/05
[#50594] Re: [ruby-trunk - Feature #7517] Fixnum::MIN,MAX
— Charles Oliver Nutter <headius@...>
2012/12/05
On Wed, Dec 5, 2012 at 12:24 PM, shyouhei (Shyouhei Urabe)
[#50636] [ruby-trunk - Bug #7528][Open] CSV.== fails to check object type — "SteveW (Stephen Wattam)" <stephenwattam@...>
6 messages
2012/12/06
[#50645] [ruby-trunk - Bug #7530][Open] Concurrent loads fail with mutex errors — "headius (Charles Nutter)" <headius@...>
7 messages
2012/12/06
[#50660] [ruby-trunk - Feature #4085] Refinements and nested methods — "trans (Thomas Sawyer)" <transfire@...>
3 messages
2012/12/07
[#50699] Commit access for Yehuda Katz — Aaron Patterson <tenderlove@...>
Hi,
4 messages
2012/12/08
[#50923] Re: Commit access for Yehuda Katz
— Charles Oliver Nutter <headius@...>
2012/12/16
I will +1 this, unsure if it has happened already (it's "catch up on
[#50733] [ruby-trunk - Bug #7539][Open] Misleading error message "can't convert nil into string" — "connec (Chris Connelly)" <chris@...>
8 messages
2012/12/10
[#50755] Becoming a committer — Charlie Somerville <charlie@...>
Hi ruby-core,
21 messages
2012/12/11
[#50759] Re: Becoming a committer
— Yukihiro Matsumoto <matz@...>
2012/12/11
Hi,
[#50784] Re: Becoming a committer
— Charles Oliver Nutter <headius@...>
2012/12/11
It's really this easy? If so, I'll send over my public key today :)
[#50795] Re: Becoming a committer
— Yukihiro Matsumoto <matz@...>
2012/12/11
Hi,
[#50797] Re: Becoming a committer
— Charles Oliver Nutter <headius@...>
2012/12/11
I guess there's a few things I'd be interested in:
[#50809] Re: Becoming a committer
— SASADA Koichi <ko1@...>
2012/12/12
(2012/12/12 8:55), Charles Oliver Nutter wrote:
[#50815] Re: Becoming a committer
— Charles Oliver Nutter <headius@...>
2012/12/12
On Wed, Dec 12, 2012 at 12:04 AM, SASADA Koichi <[email protected]> wrote:
[#50816] Re: Becoming a committer
— "NARUSE, Yui" <naruse@...>
2012/12/12
2012/12/12 Charles Oliver Nutter <[email protected]>:
[#50817] Re: Becoming a committer
— Charles Oliver Nutter <headius@...>
2012/12/12
On Wed, Dec 12, 2012 at 2:59 AM, NARUSE, Yui <[email protected]> wrote:
[#50765] [ruby-trunk - Bug #7544][Open] Accented characters in IRB — cfabianski (Cédric FABIANSKI) <cfabianski@...>
6 messages
2012/12/11
[#50793] [ruby-trunk - Bug #7547][Open] Dir.mktmpdir('~something') tries to expand a profile directory — "jstanley0 (Jeremy Stanley)" <jeremy@...>
4 messages
2012/12/11
[#50810] [ruby-trunk - Feature #7549][Open] A Ruby Design Process — "brixen (Brian Ford)" <brixen@...>
34 messages
2012/12/12
[#50829] [ruby-trunk - Feature #7549] A Ruby Design Process
— "subwindow (Erik Peterson)" <erik@...>
2012/12/12
[#50837] [ruby-trunk - Feature #7549] A Ruby Design Process
— "subwindow (Erik Peterson)" <erik@...>
2012/12/12
[#50867] [ruby-trunk - Bug #7556][Assigned] test error on refinement — "usa (Usaku NAKAMURA)" <usa@...>
14 messages
2012/12/13
[#50900] [ruby-trunk - Bug #7564][Open] r38175 introduces incompatibility — "tenderlovemaking (Aaron Patterson)" <aaron@...>
14 messages
2012/12/14
[#50913] [ruby-trunk - Bug #7568][Open] Yaml fails to encode zero date string. — "anshul (Anshul Khandelwal)" <anshul@...>
5 messages
2012/12/15
[#50920] [ruby-trunk - Bug #7568][Assigned] Yaml fails to encode zero date string.
— "charliesome (Charlie Somerville)" <charlie@...>
2012/12/16
[#50988] Re: [ruby-trunk - Bug #7568][Assigned] Yaml fails to encode zero date string.
— Aaron Patterson <tenderlove@...>
2012/12/19
On Sun, Dec 16, 2012 at 12:53:14PM +0900, charliesome (Charlie Somerville) wrote:
[#51015] 1.9.3 patch level release — Zachary Scott <zachary@...>
I know unak-san was asking about a 1.9.3 patch level release, so I
8 messages
2012/12/20
[#51099] [ruby-trunk - Feature #7612][Open] Enumerators take a proc — "pedz (Perry Smith)" <pedz@...>
4 messages
2012/12/23
[ruby-core:51094] [ruby-trunk - Feature #7604] Make === comparison operator ability to delegate comparison to an argument
From:
"prijutme4ty (Ilya Vorontsov)" <prijutme4ty@...>
Date:
2012-12-23 15:49:42 UTC
List:
ruby-core #51094
Issue #7604 has been updated by prijutme4ty (Ilya Vorontsov).
boris_stitnicky (Boris Stitnicky) wrote:
> Your proposal reminds me of trying to extend #coerce behavior. What you call "mirroring", happens with #coerce. "Double mirrorring" is prevented by simply by #coerce being required to return a compatible pair. That being said, I did have times, when I wanted operator-specific #coerce (eg. different physical quantities do not add or compare, but do multiply). Essentially, you are proposing:
>
> (1.) Let us have operator-specific #coerce (for #=== at least).
> (2.) Let us have #=== actually using its specific coerce for some chosen argument types.
>
> To me, achieving (1.) is imaginable as either #coerce taking an optional second argument, as in other.coerce( self, :=== ), or as having special #coerce_plus, #coerce_asterisk, #coerce_double_equal_sign, #coerce_triple_equal_sign etc.
>
> Achieving (2.) is more difficult. As you pointed out, many classes have their own #===. But it is a general case that operator methods should be written with #coerce in mind.
>
> Having thus reframed your proposal, let me also express my personal opinion about it: I would be in favor of cautiously implementing (1.), while (2.) means a bit work for everyone. I noticed that Marc Andre was also concerned about #coerce specification.
I like the idea of #coerce having additional argument(first time I thought whether current behavior of coerce can help me in solving this problem). Coercion implies that code of operators like + or === in built-in should be changed as in (2) case. I think that your solution can be actually much more flexible than mine. Also I can't realize any benefits of (2) over (1).
----------------------------------------
Feature #7604: Make === comparison operator ability to delegate comparison to an argument
https://bugs.ruby-lang.org/issues/7604#change-35029
Author: prijutme4ty (Ilya Vorontsov)
Status: Open
Priority: Normal
Assignee:
Category:
Target version:
=begin
I propose to expand default behaviour of === operator in the following way:
Objects have additional instance method Object#reverse_comparison?(other) which is false by default in all basic classes.
Each class that overrides Object#===(other) should check whether reverse_comparison? is true or false
If it is false, behavior is not changed at all.
If it is true, comparison is delegated to === method of an argument with self as an argument.
This technique can help in constructing RSpec-style matchers for case statement. Example:
# usual method call
arr = %w[cat dog rat bat]
puts arr.end_with?(%w[dog bat]) # ==> false
puts arr.end_with?(%w[rat bat]) # ==> true
puts arr.end_with?(%w[bat]) # ==> true
# predicate-style case
case %w[cat dog rat bat].end_with?
when %w[dog bat]
puts '..., dog, bat'
when %w[rat bat]
puts '..., rat, bat'
when %w[bat]
puts '..., bat'
else
puts 'smth else'
end
# ==> ..., rat, bat
Code needed to run this is not very complex:
class Object
def reverse_comparison?(other)
false
end
alias_method :'old===', :'==='
def ===(other)
(other.reverse_comparison?(self) ? (other.send 'old===',self) : (self.send 'old===',other))
end
end
class Predicate
def initialize(&block)
@block = block
end
def reverse_comparison?(other)
true
end
def ===(*args)
@block.call(*args)
end
end
class Array
alias_method :'old===', :'==='
def ===(other)
other.reverse_comparison?(self) ? (other.send('===',self)) : (self.send('old===',other))
end
def end_with?(expected_elements = nil)
return last(expected_elements.size) == expected_elements if expected_elements
Predicate.new{|suffix| last(suffix.size) == suffix }
end
end
This technique looks powerful and beautiful for me. One detail is that obj#reverse_comparison? can distinguish different types of arguments and returns true only for certain types of given object. Also this can be used to prevent double-mirroring (as shown below)
The problem is that many base classes already defined custom === operator, so each of those classes (Fixnum, Float, String, Regexp, Range etc) should be redefined in such a way to make a solution full-fledged.
Another problem is case that both objects defined reverse_comparison? to return true. In my solution Predicate#=== just ignores result of revese_comparison? which is not consistent.
Another possible way is to raise errors on double mirroring:
def reverse_comparison?(other)
raise 'double mirroring' if @__mirroring_started
@__mirroring_started = true
return true unless other.reverse_comparison?(self)
false
ensure
remove_instance_variable :@__mirroring_started
end
My proposal is to add reverse_comparison? method and change base classes operator === to use its result as shown above. May be it's worth also to make a class analogous to Predicate in stdlib.
=end
--
http://bugs.ruby-lang.org/