[#43077] problems committing — Aaron Patterson <tenderlove@...>
It seems like the disk might be full on the svn server:
5 messages
2012/03/05
[#43090] "\\".gsub("\\", "\\\\") == "\\" ?!!! — Rodrigo Rosenfeld Rosas <rr.rosas@...>
Please, help me understand what is happening here.
6 messages
2012/03/06
[#43094] Re: "\\".gsub("\\", "\\\\") == "\\" ?!!!
— Xavier Noria <fxn@...>
2012/03/06
A literal passed as second argument to gsub goes over two
[#43120] [ruby-trunk - Bug #6124][Open] What is the purpose of "fake" gems in Ruby — Vit Ondruch <v.ondruch@...>
27 messages
2012/03/07
[#43142] Questions about thread performance (with benchmark included) — Rodrigo Rosenfeld Rosas <rr.rosas@...>
A while ago I've written an article entitled "How Nokogiri and JRuby
10 messages
2012/03/08
[#43785] Re: Questions about thread performance (with benchmark included)
— Tomoyuki Chikanaga <nagachika00@...>
2012/03/28
Hello, Rodrigo.
[#43797] Re: Questions about thread performance (with benchmark included)
— Rodrigo Rosenfeld Rosas <rr.rosas@...>
2012/03/28
Em 27-03-2012 23:22, Tomoyuki Chikanaga escreveu:
[#44213] Re: Questions about thread performance (with benchmark included)
— SASADA Koichi <ko1@...>
2012/04/09
Hi,
[#44214] Re: Questions about thread performance (with benchmark included)
— Urabe Shyouhei <shyouhei@...>
2012/04/09
#### MRI threads myths and facts #####
[#44220] Re: Questions about thread performance (with benchmark included)
— Rodrigo Rosenfeld Rosas <rr.rosas@...>
2012/04/09
Hi Urabe, thank you for your input, but I think you have
[#43163] Help w/ some C to create NullClass — trans <transfire@...>
I am trying to write a C extension for "NullClass" functionality. I've
3 messages
2012/03/10
[#43245] [ruby-trunk - Bug #6131][Open] Ctrl-C handler do not work from exec process (Windows) — Luis Lavena <luislavena@...>
10 messages
2012/03/12
[#43279] [ruby-trunk - Bug #6148][Open] ruby_1_9_3 revision conflict — Jon Forums <redmine@...>
4 messages
2012/03/14
[#43313] [ruby-trunk - Feature #6150][Open] add Enumerable#grep_v — Suraj Kurapati <sunaku@...>
17 messages
2012/03/15
[#43325] [ruby-trunk - Bug #6154][Open] Eliminate extending WaitReadable/Writable at runtime — Charles Nutter <headius@...>
25 messages
2012/03/16
[#43369] Re: [ruby-trunk - Bug #6154][Open] Eliminate extending WaitReadable/Writable at runtime
— Tanaka Akira <akr@...>
2012/03/17
2012/3/16 Charles Nutter <[email protected]>:
[#43326] [ruby-trunk - Bug #6154] Eliminate extending WaitReadable/Writable at runtime
— Charles Nutter <headius@...>
2012/03/16
[#43334] [ruby-trunk - Bug #6155][Open] Enumerable::Lazy#flat_map raises an exception when an element does not respond to #each — Dan Kubb <dan.kubb@...>
9 messages
2012/03/16
[#43345] [ruby-trunk - Bug #6159][Open] Enumerable::Lazy#inspect — Benoit Daloze <redmine@...>
10 messages
2012/03/16
[#43497] [ruby-trunk - Bug #6179][Open] File::pos broken in Windows 1.9.3p125 — "jmthomas (Jason Thomas)" <jmthomas@...>
24 messages
2012/03/20
[#43502] [ruby-trunk - Feature #6180][Open] to_b for converting objects to a boolean value — "AaronLasseigne (Aaron Lasseigne)" <aaron.lasseigne@...>
17 messages
2012/03/20
[#43529] [ruby-trunk - Bug #6183][Open] Enumerator::Lazy performance issue — "gregolsen (Innokenty Mikhailov)" <anotheroneman@...>
36 messages
2012/03/21
[#43814] [ruby-trunk - Feature #6219][Open] Return value of Hash#store — "MartinBosslet (Martin Bosslet)" <Martin.Bosslet@...>
20 messages
2012/03/28
[#43904] [ruby-trunk - Feature #6225][Open] Hash#+ — "trans (Thomas Sawyer)" <transfire@...>
36 messages
2012/03/29
[#43923] [ruby-trunk - Feature #6225] Hash#+
— "shyouhei (Shyouhei Urabe)" <shyouhei@...>
2012/03/30
[#43909] [ruby-trunk - Feature #6225][Assigned] Hash#+
— "mame (Yusuke Endoh)" <mame@...>
2012/03/29
[#43920] [ruby-trunk - Feature #6225] Hash#+
— "shyouhei (Shyouhei Urabe)" <shyouhei@...>
2012/03/30
[#43951] [ruby-trunk - Bug #6228][Open] [mingw] Errno::EBADF in ruby/test_io.rb on ruby_1_9_3 — "jonforums (Jon Forums)" <redmine@...>
28 messages
2012/03/30
[#43996] [ruby-trunk - Bug #6236][Open] WEBrick::HTTPServer swallows Exception — "regularfry (Alex Young)" <alex@...>
13 messages
2012/03/31
[#44015] [Ruby 1.8 - Bug #6239][Open] super Does Not Pass Modified Rest Args When Originally Empty — "mudge (Paul Mucur)" <mudge@...>
6 messages
2012/03/31
[ruby-core:43431] [ruby-trunk - Feature #4102] Proposal for 'let'. A new approach using block-defaults in 1.9
From:
nahi <nakahiro@...>
Date:
2012-03-18 09:44:28 UTC
List:
ruby-core #43431
Issue #4102 has been updated by nahi.
Description updated
Category set to core
Assignee set to matz
----------------------------------------
Feature #4102: Proposal for 'let'. A new approach using block-defaults in 1.9
https://bugs.ruby-lang.org/issues/4102#change-24750
Author: banister
Status: Open
Priority: Normal
Assignee: matz
Category: core
Target version:
=begin
This is a very simple function, it would be implemented as follows:
module Kernel
private
def let() yield end
end
First of all, do not dismiss this functionality out of hand because of
its simplicity.
Even though it is just a 'yield', when it is combined with Ruby 1.9's
block defaults and new block-variable scoping rules it is actually quite
powerful and it behaves exactly like a let* in lisp.
Some advantages of this functionality are:
(1) Gives you precise control over the scope of your variables.
I note that after the publication of "Metaprogramming in Ruby" by Paolo
Perrotta the following idiom has started to appear:
proc do
..my code..
end.call
It is used exactly as the proposed 'let' would be used, but is
syntactically much uglier.
Yes, i know an alternative is to just make shorter and smaller methods.
But is the ability to control and restrict scope ever a bad thing?
(2) Testing and teaching about blocks.
As the proposed 'let' simply yields to a block it can be used to
illustrate block behaviour and block concepts to a new Ruby programmer.
It also may be useful to an experienced programmer when trying out new
ideas.
Here are some example uses of the proposed 'let':
Example 1: Carve out a temporary scope, make 'x' local to that scope
x = :outer
let { |x| x = :inner } #=> :inner
x #=> :outer
Example 2: Here we use Ruby 1.9's block-defaults to make 'y' block-local
and give it a value:
let { |y=10| y } #=> 10
Example 3: Make 'x' and 'y' block-local and have 'y' value depend on 'x'
(equivalent to let* in lisp)
let { |x=10, y=(2*x)| [x, y] } #=> [10, 20]
In summary, I think this proposal should succeed for the following
reasons:
(1) It is an exceptionally simple implementation.
(2) More control over scope is never a bad thing.
(3) I have seen people re-implementing this functionality themselves
using: proc { ..code.. }.call
(4) It is very useful for teaching and testing block behaviour.
Thanks,
John
=end
--
http://bugs.ruby-lang.org/