Nabble - ruby-talk

Re: Good or best way to allocate a large array

2009-11-09T15:06:23Z

On Mon, Nov 9, 2009 at 5:46 PM, Ralph Shnelvar <ralphs@...> wrote:
> Florian,
>
> If there is no use count, how does Ruby know that there are no
> references to the object that should be freed?

As Florian said, MRI ruby uses a mark-sweep GC algorithm, when it
needs to GC it traces out references from a set of root objects, and
marks any objects which are reachable recursively.

Then it frees any objects which aren't marked.

Reference counting might seem simpler, but it is expensive because the
count needs to be maintained everytime a reference changes, and it
can't reclaim cyclic garbage which can't be reached from a root:

a -> b -> c
^ |
*------------+

Mark/Sweep is a fairly primitive GC technique, it was probably the
second technique applied in the long history of GC. There are more
recent techniques such as generation scavenging which makes use of the
observance that most objects in a uniformly object-oriented language
like Ruby either live a very short, or a reasonably long life time
with the preponderance being short-lived. Generation scavenging
collects the short-lived objects very efficiently, and typically uses
mark-sweep less frequently to clean up the older ones.

--
Rick DeNatale

Blog: http://talklikeaduck.denhaven2.com/
Twitter: http://twitter.com/RickDeNatale
WWR: http://www.workingwithrails.com/person/9021-rick-denatale
LinkedIn: http://www.linkedin.com/in/rickdenatale

Re: Ruby doesn't implement x++ for Fixnum's because ???

2009-11-09T14:57:08Z

On Mon, Nov 9, 2009 at 2:48 PM, Aldric Giacomoni <aldric@...> wrote:
> Rick Denatale wrote:
>> Just so you know I wasn't dissing La langue belle. I try to maintain
>> a basic fluency. Not sure if my French or my C is more rusty! <G>
>>
>
> Hah! No worries, I wasn't insulted.
> So .. Friend++ ?

Bien sur

--
Rick DeNatale

Blog: http://talklikeaduck.denhaven2.com/
Twitter: http://twitter.com/RickDeNatale
WWR: http://www.workingwithrails.com/person/9021-rick-denatale
LinkedIn: http://www.linkedin.com/in/rickdenatale

Re: Good or best way to allocate a large array

2009-11-09T14:46:33Z

Florian,

If there is no use count, how does Ruby know that there are no
references to the object that should be freed?

Ralph

Monday, November 9, 2009, 3:02:37 PM, you wrote:

FF> Ralph Shnelvar wrote:
>> Marnen,
>>
>> Unless "scope" means something different in Ruby than it does in other
>> languages, it would appear that the garbage collector cannot possibly
>> free memory when something goes out of scope but, instead, when the
>> UseCount goes to zero.
>>
FF> Except that uses aren't counted in Ruby. Ruby has a mark-and-sweep
FF> garbage collector. When Ruby runs out of memory a garbage collection run
FF> is triggered. If there aren't any references to the objects in question
FF> left, they aren't reachable from the root set and thus not marked in the
FF> first phase of GC, in the second phase they will then (too be
FF> conservative: most likely) be freed.

--
Best regards,
Ralph mailto:ralphs@...

Re: Good or best way to allocate a large array

2009-11-09T14:42:51Z

Robert,

Doesn't that just move things into a BiNum ... which is not native 64?

Ralph

Monday, November 9, 2009, 2:35:26 PM, you wrote:

>> Does Ruby support native 64-bit quantities?

RK> Yes. You can try it out

RK> ruby1.9 -e '100.times {|i| x = 1 << i;p x, x.class}'

--
Best regards,
Ralph mailto:ralphs@...

Re: Readout and Edit Cookies

2009-11-09T14:18:26Z

Christian Habermann wrote:
> First I send a Form with Net::HTTP.post_form.
> Now I want to readout a Cookie and later edit it! How can I make this?

I found the solution! Mechanize
http://mechanize.rubyforge.org/mechanize/

--
Posted via http://www.ruby-forum.com/.

Re: Good or best way to allocate a large array

2009-11-09T14:02:37Z

Ralph Shnelvar wrote:
> Marnen,
>
> Unless "scope" means something different in Ruby than it does in other
> languages, it would appear that the garbage collector cannot possibly
> free memory when something goes out of scope but, instead, when the
> UseCount goes to zero.
>
Except that uses aren't counted in Ruby. Ruby has a mark-and-sweep
garbage collector. When Ruby runs out of memory a garbage collection run
is triggered. If there aren't any references to the objects in question
left, they aren't reachable from the root set and thus not marked in the
first phase of GC, in the second phase they will then (too be
conservative: most likely) be freed.

--
Florian Frank

Re: Understanding Threads...

2009-11-09T14:01:38Z

On 11/09/2009 10:24 PM, Judson Lester wrote:

> I completely agree with Jason's diagnosis. I'd like to make two
> observations, though.
>
> First, you can avoid the mutex entirely by using thread-local variables:
>
> threads << Thread.new { Thread.current[:result] = method1(string) }
>
> results = threads.inject({}) do |results, thread|
> thread.join
> results.merge(thread[:result])
> end

Even better: we have Thread.value. If you join only from a single
thread there is no additional synchronization needed:

irb(main):001:0> t = (1..5).map {|i| Thread.new(i) {|x| "value #{x}"} }
=> [#<Thread:0x9c4f618 dead>, #<Thread:0x9c4f58c dead>,
#<Thread:0x9c4f4b0 run>, #<Thread:0x9c4f424 run>, #<Thread:0x9c4f398 run>]
irb(main):002:0> t.map {|th| th.value}
=> ["value 1", "value 2", "value 3", "value 4", "value 5"]

> Second, and (possibly) more controversially, just because you can eval
> doesn't mean you should. To my eye, this looks nicer:
>
> threads = [
> Thread.new { Thread.current[:result] = method1(string) },
> Thread.new { Thread.current[:result] = method2(string) },
> Thread.new { Thread.current[:result] = method3(string) },
> Thread.new { Thread.current[:result] = method4(string) }
> ]
>
> And exception handling, etc, will be ever so much clearer.

You can as well do

def method(string)
threads = %w{
methodname1
methodname2
methodname3
methodname4
}.map do |method|
Thread.new(method) do |m|
send(m, string) # each method call makes an HTTP request
end.map {|th| th.value}
end

and be done.

Kind regards

robert

--
remember.guy do |as, often| as.you_can - without end
http://blog.rubybestpractices.com/

Re: wrong number of arguments in initialize

2009-11-09T13:51:32Z

Arti Singh wrote:
> I tried to initalize my methods and I get an error
> def initialize(name,browser,username)
>
You define intialize to ask for 3 arguments, you don't give any of them
defaults.....

> @s_name=name
> @browser=browser
> @username=username
> end #def initialize(dc)
>
> attr_accessor :name,:browser,:username
>
>
>
>
> C:/RubyInstall/ruby/lib/ruby/1.8/test/unit/testcase.rb:59:in
> `initialize': wrong number of arguments (1 for 3) (ArgumentError)
>
>

You don't show where you call the initialize method, but the error says

you only gave one argument, and that it was called on line 59...
> I honestly dont get it now, this is silly
>

I get bit by this one all the time :)

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Re: FXRuby table and color questions

2009-11-09T13:51:02Z

On Mon, Nov 9, 2009 at 1:38 PM, Leslie Viljoen <leslieviljoen@...> wrote:

> Does the Fox toolkit support partial transparency?

Not as far as I know.

When you assign an icon image to a widget (usually a label or button),
FOX will honor any regions identified as fully transparent in the
image. For PNGs, it uses the alpha channel to identify regions where
alpha is zero; for other image types it can guess the transparent
color or you can specify it explicitly.

> Also, is it possible to give different background colours to each cell
> in a FXTable? The documentation seems to
> skirt past this issue with a setCellColor function which only provides
> for global shading of every second row/col.
> Maybe I am missing something obvious?

You aren't missing anything. All you can achieve with the table, short
of maybe subclassing it and overriding the drawing behavior, is set
alternating cell colors.

Re: FileString - request for comments

2009-11-09T13:50:00Z

-------- Original-Nachricht --------
> Datum: Tue, 10 Nov 2009 06:25:08 +0900
> Von: Robert Klemme <shortcutter@...>
> Betreff: Re: FileString - request for comments

> A good point! You're probably right and I was too pessimistic. I'd
> love to see
>
> fs[/foo(\w+)/, 1] = "bar"
> fs.gsub! /foo/, "bar"
>
> etc. because those would be the ones that would make FileString
> convenient for me. :-)

Those already exist. Unfortunately optimizing regex matching is too involved as that I could have done that in 24h :)
Means fs[/foo(\w+)/, 1] = "bar" is just more convenient than writing:
data = File.read
data[/foo(\w+)/, 1] = "bar"
File.open(path, "w") { |fh| fh.write(data) }
But I think that's already quite worth it :)
I mean - that's just lots of boilerplate.

> Thanks for listening and sharing!

Always :D
The listening part has made me change the docs btw., I know hint on thinking about performance and probably just use a string and write back when all is done.

Regards
Stefan
--
Jetzt kostenlos herunterladen: Internet Explorer 8 und Mozilla Firefox 3.5 -
sicherer, schneller und einfacher! http://portal.gmx.net/de/go/atbrowser

wxRuby - tabular data with extra widgets

2009-11-09T13:49:03Z

Hi,

I am needing to display a table of data.
I need to be able to sort the columns by clicking the label at the
top (ideally such that one click sorts ascending, the next descending
etc etc)
I need grid lines.
I need to be able to include drop down lists in multiple columns,
such that selecting the drop down will change columns in the same row.

This data is backed by active record, and I have active support etc
available.

My first thought was to use Wx::Grid, but I don't have the first
idea how to go about getting a drop down into a column.

My second thought is to use a grid sizer of some sort, but that
would mean creating my own buttons for the column headers, doing
something to get a grid etc etc.

What other options to I have? Or how do I go about 1)?

All pointers appreciated!

Current source is at
http://codaset.com/nevynxxx/wxrcg/source/master/blob/lib/views/dm_screen_frame.rb

Regards

Anthony

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Re: Good or best way to allocate a large array

2009-11-09T13:35:26Z

On 11/09/2009 06:25 PM, Ralph Shnelvar wrote:
> Newbie here:
>
> I will want/need to create an array of approximately 300K rows and 20
> columns. The array will be an array of either 32-bit quantities or 64-bit quantities.

So we are talking about 300,000 * 20 * 8 ~ 48MB which does not sound too
large.

robert@fussel:~$ time ruby1.9 -e 'x=1<<63;Array.new(300_000*20) {x}'

real 0m1.922s
user 0m1.288s
sys 0m0.032s
robert@fussel:~$ time ruby1.9 -e 'x=1<<63;Array.new(300_000*20) {1<<63}'

real 0m7.143s
user 0m6.668s
sys 0m0.204s

> Does Ruby support native 64-bit quantities?

Yes. You can try it out

ruby1.9 -e '100.times {|i| x = 1 << i;p x, x.class}'

> What's a good/best way to to create such an array. Is there a way to
> tell Ruby, "OK, I'm done with this array."

No need to: if there are no more live references to that Array it will
get collected eventually.

> Can one create such an array such that the garbage collector can
> free the memory in one fast operation?

Probably not because of the number of objects in the Array (if they are
all Fixnums it will probably a bit faster.

The question is, what do you do with that huge Array? Chances are that
you need to allocate more memory during processing. What's your use
case? A database might be an option or a flat file - it all depends.

Kind regards

robert

--
remember.guy do |as, often| as.you_can - without end
http://blog.rubybestpractices.com/

Re: [ANN] called_from 0.1.0 released

2009-11-09T13:31:31Z

I've long wished that caller returned an array of BacktraceLine... likewise
Exception#backtrace.

class BacktraceLine
attr_reader :line, :file, :method, :arguments
end

Not sure if it's a daydream or an REP...

Judson

On Sun, Nov 8, 2009 at 4:51 PM, Jeremy Kemper <jeremy@...> wrote:

> This is probably the most common usage of Kernel#caller. You've made
> it more useful and much faster -- great extension!
>
> jeremy
>
> On Sun, Nov 8, 2009 at 3:25 PM, makoto kuwata <kwatch@...> wrote:
> > I releaded called_from 0.1.0.
> > http://github.com/kwatch/called_from
> >
> > Kernel#caller() is very useful, but very slow.
> > 'called_from' solves this problem.
> >
> >
> > About
> > -----
> >
> > 'called_from' provides called_from() global function
> > which gets filename and line number of caller.
> >
> > In short:
> >
> > require 'called_from'
> > filename, linenum, function = called_from(1)
> >
> > is equivarent to:
> >
> > caller(1)[0] =~ /:(\d+)( in `(.*)')?/
> > filename, linenum, function = $`, $1, $2
> >
> > But called_from() is much faster than caller()[0].
> >
> >
> >
> > Example
> > -------
> >
> > require 'called_from'
> >
> > ##
> > ## report not only what sql is queried but also from where query()
> > is called.
> > ## (this is very convenient for development and debugging)
> > ## in such examle, speed of called_from() is very important.
> > ##
> > def query(sql)
> > filename, linenum, function = called_from()
> > log.debug("#{Time.now}: #{sql} (called from #{filename}:#
> > {linenum})")
> > return connection.query(sql)
> > end
> >
> > ##
> > ## if cache data is older than template file's timestamp,
> > ## refresh cache data.
> > ## it is very important that called_from() is much faster than
> > caller()[0]
> > ## because speed is necessary for caching.
> > ##
> > def cache_helper(cache_key)
> > ## check template file's timestamp
> > template_filename, linenum, function = called_from()
> > timestamp = File.mtime(template_filename)
> > ## if cache data is newer than template's timestamp, return data
> > data = @cache.get(cache_key, :timestamp=>timestamp)
> > return data if data
> > ## if cache data is older than template's timestamp, refresh it
> > data = yield()
> > @cache.set(cache_key, data)
> > return data
> > end
> >
> >
> >
> > Benchmark
> > ---------
> >
> > Here is an example result of benchmark on Merb application.
> > This shows that called_from() is more than 30 times faster than caller
> > ()[0].
> >
> >
> > *** n=100000
> > user system total
> > real
> > caller()[0] 7.920000 0.400000 8.320000
> > ( 8.985343)
> > caller()[0] (*1) 8.590000 0.420000 9.010000
> > ( 9.804065)
> > called_from() 0.240000 0.010000 0.250000
> > ( 0.257151)
> > called_from() (*2) 0.250000 0.000000 0.250000
> > ( 0.268603)
> >
> >
> > (*1) retrieve filename and line number using pattern match (=~ /:
> > (\d+)/)
> > (*2) retrieve filename and line number
> >
> >
> >
> > Installation
> > ------------
> >
> > $ sudo gem install called_from
> >
> > Or
> >
> > $ tar xzf called_from_X.X.X.tar.gz
> > $ cd called_from_X.X.X/
> > $ ruby setup.rb config
> > $ ruby setup.rb setup
> > $ sudo ruby setup.rb install
> >
> > Notice: called_from is implemented in both C-extention and pure Ruby.
> > C-extention is available on UNIX-like OS and Ruby 1.8.x.
> >
> >
> > --
> > regards,
> > makoto kuwata
> >
> >
>
>

Re: FileString - request for comments

2009-11-09T13:25:08Z

On 09.11.2009 17:29, apeiros@... wrote:
> -------- Original-Nachricht --------
>> Von: Robert Klemme <shortcutter@...>
> As all highlevel things. If you don't know the things you're dealing with you can easily kill performance. Consider e.g. ary.any? { |obj| other.include?(obj) } - there, just accidentally created an O(n^2) algorithm. It can happen everywhere and it can look totally innocent.
> That's not a problem that's specific to FileString but to everything that's abstract.

True.

>> And although at a certain level of abstraction a file and a
>> String are pretty much the same (sequence of chars / bytes) it may
>> actually be a good thing to keep the API separate in order to treat
>> both appropriately. Stefan, what's your experience?
>
> As you see, I disagree :)

> However, what you say is of course correct. Using FileString means
you > have to keep in mind that you're dealing with a file.
> But: if you know you're dealing with a file, it can even help you
> making things faster. For example, if you indeed want to compare two
> files for equality, FileString#== will be faster and less memory
> intensive than you doing File.read(a) == File.read(b) if the two
files > are big.

A good point! You're probably right and I was too pessimistic. I'd
love to see

fs[/foo(\w+)/, 1] = "bar"
fs.gsub! /foo/, "bar"

etc. because those would be the ones that would make FileString
convenient for me. :-)

> Thanks for your thoughts robert, much appreciated

Thanks for listening and sharing!

Kind regards

robert

--
remember.guy do |as, often| as.you_can - without end
http://blog.rubybestpractices.com/

Re: Understanding Threads...

2009-11-09T13:24:42Z

I completely agree with Jason's diagnosis. I'd like to make two
observations, though.

First, you can avoid the mutex entirely by using thread-local variables:

threads << Thread.new { Thread.current[:result] = method1(string) }

results = threads.inject({}) do |results, thread|
thread.join
results.merge(thread[:result])
end

Second, and (possibly) more controversially, just because you can eval
doesn't mean you should. To my eye, this looks nicer:

threads = [
Thread.new { Thread.current[:result] = method1(string) },
Thread.new { Thread.current[:result] = method2(string) },
Thread.new { Thread.current[:result] = method3(string) },
Thread.new { Thread.current[:result] = method4(string) }
]

And exception handling, etc, will be ever so much clearer.

Judson

On Mon, Nov 9, 2009 at 1:14 PM, Jason Roelofs <jameskilton@...> wrote:

> On Mon, Nov 9, 2009 at 3:45 PM, Matt White <mattw922@...> wrote:
>
> > I am writing an app that retrieves multiple web pages in one method
> > call. Threading has improved performance drastically for me, but I
> > need some help understanding how exactly the call to join is going to
> > affect my program.
> >
> > Here's some code:
> >
> > def method(string)
> > result = {}
> > mutex = Mutex.new
> > threads = []
> >
> > %w{methodname1 methodname2 methodname3 methodname4}.each do |method|
> > threads << Thread.new(method) do |m|
> > r = eval("#{m}(string)") # each method call makes an HTTP
> > request
> > mutex.synchronize { result.merge!(r) }
> > end
> > end
> > threads.each { |t| t.join }
> > result
> > end
> >
> > Seems like the call to join on each thread is necessary to keep the
> > script from getting ahead of itself, but if I exclude that line, it
> > doesn't seem to hurt my results and the program runs a lot faster.
> > Also, sometimes I get deadlocked somehow if I do use the call to join
> > and I'm not certain as to why. Can someone help shed some light on the
> > situation? Do I need to call join? Any idea why I'm deadlocking?
> > Thanks!
> >
> >
> Thread#join simply says "Wait here until this thread has finished
> executing".
>
> So what you're doing is waiting for all threads to finish before execution
> continues, aka blocking main thread execution. Without the #join, the
> values
> in results will be nonderministic. Any perceived deadlocking is probably
> whatever is in your eval call not timing out. You'll have to watch out
> carefully for that.
>
> Jason
>

wrong number of arguments in initialize

2009-11-09T13:18:24Z

I tried to initalize my methods and I get an error
def initialize(name,browser,username)
@s_name=name
@browser=browser
@username=username
end #def initialize(dc)
attr_accessor :name,:browser,:username

C:/RubyInstall/ruby/lib/ruby/1.8/test/unit/testcase.rb:59:in
`initialize': wrong number of arguments (1 for 3) (ArgumentError)

I honestly dont get it now, this is silly
--
Posted via http://www.ruby-forum.com/.

Re: Understanding Threads...

2009-11-09T13:14:33Z

On Mon, Nov 9, 2009 at 3:45 PM, Matt White <mattw922@...> wrote:

> I am writing an app that retrieves multiple web pages in one method
> call. Threading has improved performance drastically for me, but I
> need some help understanding how exactly the call to join is going to
> affect my program.
>
> Here's some code:
>
> def method(string)
> result = {}
> mutex = Mutex.new
> threads = []
>
> %w{methodname1 methodname2 methodname3 methodname4}.each do |method|
> threads << Thread.new(method) do |m|
> r = eval("#{m}(string)") # each method call makes an HTTP
> request
> mutex.synchronize { result.merge!(r) }
> end
> end
> threads.each { |t| t.join }
> result
> end
>
> Seems like the call to join on each thread is necessary to keep the
> script from getting ahead of itself, but if I exclude that line, it
> doesn't seem to hurt my results and the program runs a lot faster.
> Also, sometimes I get deadlocked somehow if I do use the call to join
> and I'm not certain as to why. Can someone help shed some light on the
> situation? Do I need to call join? Any idea why I'm deadlocking?
> Thanks!
>
>

Thread#join simply says "Wait here until this thread has finished
executing".

So what you're doing is waiting for all threads to finish before execution
continues, aka blocking main thread execution. Without the #join, the values
in results will be nonderministic. Any perceived deadlocking is probably
whatever is in your eval call not timing out. You'll have to watch out
carefully for that.

Jason

Understanding Threads...

2009-11-09T12:45:06Z

I am writing an app that retrieves multiple web pages in one method
call. Threading has improved performance drastically for me, but I
need some help understanding how exactly the call to join is going to
affect my program.

Here's some code:

def method(string)
result = {}
mutex = Mutex.new
threads = []

%w{methodname1 methodname2 methodname3 methodname4}.each do |method|
threads << Thread.new(method) do |m|
r = eval("#{m}(string)") # each method call makes an HTTP
request
mutex.synchronize { result.merge!(r) }
end
end
threads.each { |t| t.join }
result
end

Seems like the call to join on each thread is necessary to keep the
script from getting ahead of itself, but if I exclude that line, it
doesn't seem to hurt my results and the program runs a lot faster.
Also, sometimes I get deadlocked somehow if I do use the call to join
and I'm not certain as to why. Can someone help shed some light on the
situation? Do I need to call join? Any idea why I'm deadlocking?
Thanks!

Re: Good or best way to allocate a large array

2009-11-09T12:33:17Z

Marnen,

Unless "scope" means something different in Ruby than it does in other
languages, it would appear that the garbage collector cannot possibly
free memory when something goes out of scope but, instead, when the
UseCount goes to zero.

Ralph

Monday, November 9, 2009, 12:31:21 PM, you wrote:

MLK> Ralph Shnelvar wrote:
>> Marnen,
>>
>> I am a Ruby newbie but as far as I know, memory gets freed when the
>> garbage collector gets around to doing it.

MLK> Right. And as far as I know, it will do that when the object goes out
MLK> of scope.

>>
>> Ralph
>>
>>
>> MLK> The answer to both questions: as far as I know, it will be
>> deallocated
>> MLK> when it goes out of scope.
MLK> Best,
MLK> --
MLK> Marnen Laibow-Koser
MLK> http://www.marnen.org
MLK> marnen@...

--
Best regards,
Ralph mailto:ralphs@...

Readout and Edit Cookies

2009-11-09T12:05:39Z

First I send a Form with Net::HTTP.post_form.
Now I want to readout a Cookie and later edit it! How can I make this?
--
Posted via http://www.ruby-forum.com/.

Re: Ruby doesn't implement x++ for Fixnum's because ???

2009-11-09T11:48:13Z

Rick Denatale wrote:
> Just so you know I wasn't dissing La langue belle. I try to maintain
> a basic fluency. Not sure if my French or my C is more rusty! <G>
>

Hah! No worries, I wasn't insulted.
So .. Friend++ ?
Warning: incrementing a constant!
--
Posted via http://www.ruby-forum.com/.

Re: Berkeley DB BDB Install on Windows

2009-11-09T11:40:11Z

On Nov 9, 11:45 am, david <davidho...@...> wrote:

> I've been scripting in Ruby (and Rails) for about two years now, but
> have never gotten into the internals of the module/gem side. I've
> created a Ruby script using SQLite3 which works well for small data
> sets but has a performance issue when dealing with a large amount of
> data. I'm hoping to try the Berkeley DB.
>
> To start, the environment is the following.
>
> Windows XP
> Berkeley DB 4.8.24
> ruby 1.8.6-27 (http://rubyinstaller.org)
> devkit-3.4.5r3-20090411 (http://rubyinstaller.org/addons.html)
> bdb-0.6.5
>

That will not work.

DevKit has been prepared to work with newer RubyInstaller releases,
not the old One-Click ones. That is because One-Click has been
compiled with VC6 and RubyInstaller with GCC, Ruby needs to use the
same compiler.

Using the correct version of Ruby with the DevKit will allow you use --
with-db-dir option pointing to the root of the compiled BDB libraries
(which seems you didn't extract or installed).

So, first:

* Get the proper Ruby and DevKit
* Get BDB binaries and development dependencies
* Unpack them in a directory you remember
* Unpack the bdb extension
* Proceed with extconf and the proper compilation options.

HTH,
--
Luis Lavena

FXRuby table and color questions

2009-11-09T11:38:43Z

Hi people!

Does the Fox toolkit support partial transparency? None of the
documentation I read mentions it
explicitly, but there's this page here:
http://www.fxruby.org/doc/ch03s05.html showing (at the bottom) the
really ugly
results of binary-mask type transparency.

Also, is it possible to give different background colours to each cell
in a FXTable? The documentation seems to
skirt past this issue with a setCellColor function which only provides
for global shading of every second row/col.
Maybe I am missing something obvious?

Re: Ruby doesn't implement x++ for Fixnum's because ???

2009-11-09T11:35:39Z

Just so you know I wasn't dissing La langue belle. I try to maintain
a basic fluency. Not sure if my French or my C is more rusty! <G>

On Mon, Nov 9, 2009 at 2:30 PM, Aldric Giacomoni <aldric@...> wrote:

> Rick Denatale wrote:
>>
>> In French une langue denotes the same concept as tongue in English.
>> The primary meaning is that muscle in the middle of a mouth. It can
>> also mean a language
>
> Okay, I knew that...
>
>> The French un Langage is first what is used by humans to express their
>> thoughts and sentiments by means of "articulations of the voice", by
>> extension it also can mean written language, the 'language' of animals
>> (bird song, dog's barking etc.) and finally a system of communication
>> by any means "The symbolic language of flowers." "Pantomime is a
>> silent language." these last being translated examples from Le
>> Dictionnaire.
>
> By Jove! Getting lessons in my mother idiom (*grin*) on a Ruby forum. I
> knew I was following you on Twitter for a reason.
> --
> Posted via http://www.ruby-forum.com/.
>
>

--
Rick DeNatale

Blog: http://talklikeaduck.denhaven2.com/
Twitter: http://twitter.com/RickDeNatale
WWR: http://www.workingwithrails.com/person/9021-rick-denatale
LinkedIn: http://www.linkedin.com/in/rickdenatale

Re: Good or best way to allocate a large array

2009-11-09T11:31:21Z

Ralph Shnelvar wrote:
> Marnen,
>
> I am a Ruby newbie but as far as I know, memory gets freed when the
> garbage collector gets around to doing it.

Right. And as far as I know, it will do that when the object goes out
of scope.

>
> Ralph
>
>
> MLK> The answer to both questions: as far as I know, it will be
> deallocated
> MLK> when it goes out of scope.
Best,
--
Marnen Laibow-Koser
http://www.marnen.org
marnen@...
--
Posted via http://www.ruby-forum.com/.

Re: Ruby doesn't implement x++ for Fixnum's because ???

2009-11-09T11:30:11Z

Rick Denatale wrote:
>
> In French une langue denotes the same concept as tongue in English.
> The primary meaning is that muscle in the middle of a mouth. It can
> also mean a language

Okay, I knew that...

> The French un Langage is first what is used by humans to express their
> thoughts and sentiments by means of "articulations of the voice", by
> extension it also can mean written language, the 'language' of animals
> (bird song, dog's barking etc.) and finally a system of communication
> by any means "The symbolic language of flowers." "Pantomime is a
> silent language." these last being translated examples from Le
> Dictionnaire.

By Jove! Getting lessons in my mother idiom (*grin*) on a Ruby forum. I
knew I was following you on Twitter for a reason.
--
Posted via http://www.ruby-forum.com/.

Re: FileString - request for comments

2009-11-09T11:27:03Z

Eleanor McHugh wrote:
[...]
> Using a given representation just because it's unit testing friendly
> isn't necessarily a good idea...

...or necessarily a bad idea. There's something to be said for letting
architecture emerge from testability.

>
>
> Ellie
>
> Eleanor McHugh
> Games With Brains
> http://slides.games-with-brains.net
> ----
> raise ArgumentError unless @reality.responds_to? :reason

Best,
--
Marnen Laibow-Koser
http://www.marnen.org
marnen@...
--
Posted via http://www.ruby-forum.com/.

Re: Ruby doesn't implement x++ for Fixnum's because ???

2009-11-09T11:25:44Z

On Mon, Nov 9, 2009 at 11:14 AM, Aldric Giacomoni <aldric@...> wrote:

> I don't understand this block.
> Aussi, si je puis me permettre - le Francais est une langue, et Ruby est
> un langage (de programmation). Yet another one of those french
> subtleties!

Actually I think the subtleties are similar between French and English here

In French une langue denotes the same concept as tongue in English.
The primary meaning is that muscle in the middle of a mouth. It can
also mean a language, in the same sense that tongue can in English
phrases such as "His native tongue." or "Speaking in tongues."
Although such usage is more frequent in French than in English. This
is a secondary meaning though, from "Le Dictionnaire de l'Académie
Française":

LANGUE désigne aussi l’Idiome d’une nation, d’une race

And the French word idiome (another slightly false cognate) means The
language of a Nation, or province.

The French un Langage is first what is used by humans to express their
thoughts and sentiments by means of "articulations of the voice", by
extension it also can mean written language, the 'language' of animals
(bird song, dog's barking etc.) and finally a system of communication
by any means "The symbolic language of flowers." "Pantomime is a
silent language." these last being translated examples from Le
Dictionnaire.

--
Rick DeNatale

Blog: http://talklikeaduck.denhaven2.com/
Twitter: http://twitter.com/RickDeNatale
WWR: http://www.workingwithrails.com/person/9021-rick-denatale
LinkedIn: http://www.linkedin.com/in/rickdenatale

Re: Good or best way to allocate a large array

2009-11-09T11:23:12Z

Marnen,

I am a Ruby newbie but as far as I know, memory gets freed when the
garbage collector gets around to doing it.

Ralph

MLK> The answer to both questions: as far as I know, it will be deallocated
MLK> when it goes out of scope.

Re: FileString - request for comments

2009-11-09T11:19:07Z

On 9 Nov 2009, at 16:49, Ralph Shnelvar wrote:
> Robert,
>
> RK> I am still trying to wrap my head around the question whether
> hiding
> RK> file IO behind a String API is a good idea.
>
> As the PickAxe book points out, by having file i/o represented by a
> String ... that is, making it irrelevant whether one is talking to a
> String or a File ... makes for some nice unit testing.

Using a given representation just because it's unit testing friendly
isn't necessarily a good idea...

Ellie

Eleanor McHugh
Games With Brains
http://slides.games-with-brains.net
----
raise ArgumentError unless @reality.responds_to? :reason

Re: Good or best way to allocate a large array

2009-11-09T11:13:45Z

Ralph Shnelvar wrote:
> Newbie here:
>
> I will want/need to create an array of approximately 300K rows and 20
> columns. The array will be an array of either 32-bit quantities or
> 64-bit quantities.
>

Dude, you want a database. There's little reason in any language to
have an array that big.

> Does Ruby support native 64-bit quantities?

I'm not sure, but with transparent Bignum support, it doesn't matter
that much.

>
> What's a good/best way to to create such an array. Is there a way to
> tell Ruby, "OK, I'm done with this array."
>
> Can one create such an array such that the garbage collector can
> free the memory in one fast operation?

The answer to both questions: as far as I know, it will be deallocated
when it goes out of scope.

>
> Ralph

Best,
--
Marnen Laibow-Koser
http://www.marnen.org
marnen@...
--
Posted via http://www.ruby-forum.com/.

errors when using sqlite3's query and prepare methods

2009-11-09T11:09:36Z

Hello all,

I'm trying to prepare a sql statement to send to sqlite3 via ruby and
am getting errors when using the query and prepare methods. Here's my
code:

#!/usr/bin/env ruby
require 'sqlite3'
db = SQLite3::Database.new( "test.db" )

# create the database
sql = <<-eof
CREATE TABLE foobar (foo text, bar int);
INSERT INTO "foobar" VALUES('hello',1);
INSERT INTO "foobar" VALUES('world',2)
eof
db.execute_batch(sql)

# querying the database via execute works
db.execute( "select * from foobar" ) do |row|
puts row.join("\t") ;
end

# querying the database via query method does not work
db.query( "select * from foobar" ) do |row|
puts row.join("\t") ;
end

# querying the database via a prepare does not work
db.prepare( "select * from foobar" ) do |stmnt|
stmnt.execute do |row|
puts row.join("\t") ;
end
end

Below is the output from running the execute, query, and prepare methods in irb:

irb(main):036:0> # querying the database via execute works
irb(main):037:0* db.execute( "select * from foobar" ) do |row|
irb(main):038:1* puts row.join("\t") ;
irb(main):039:1* end
hello 1
world 2
=> nil
irb(main):040:0>
irb(main):041:0* # querying the database via query method does not work
irb(main):042:0* db.query( "select * from foobar" ) do |row|
irb(main):043:1* puts row.join("\t") ;
irb(main):044:1* end
NoMethodError: undefined method `join' for #<SQLite3::ResultSet:0xb7c6bae4>
from (irb):43
from /usr/lib/ruby/1.8/sqlite3/database.rb:278:in `query'
from (irb):42
irb(main):045:0>
irb(main):046:0* # querying the database via a prepare does not work
irb(main):047:0* db.prepare( "select * from foobar" ) do |stmnt|
irb(main):048:1* stmnt.execute do |row|
irb(main):049:2* puts row.join("\t") ;
irb(main):050:2* end
irb(main):051:1> end
NoMethodError: undefined method `join' for #<SQLite3::ResultSet:0xb7c3c190>
from (irb):49
from /usr/lib/ruby/1.8/sqlite3/statement.rb:166:in `execute'
from (irb):48
from /usr/lib/ruby/1.8/sqlite3/database.rb:187:in `prepare'
from (irb):47

$ ruby -v
ruby 1.8.6 (2007-09-24 patchlevel 111) [i486-linux]

$ irb -v
irb 0.9.5(05/04/13)

I've been looking at the docs[1] and the FAQ[2]. Clearly I'm
overlooking something, but what?

Thanks in advance to any pointers.

[1] http://sqlite-ruby.rubyforge.org/sqlite3/
[2] http://sqlite-ruby.rubyforge.org/sqlite3/faq.html

Regards,
- Robert

Re: Ruby doesn't implement x++ for Fixnum's because ???

2009-11-09T10:52:48Z

On Nov 9, 2009, at 12:28 PM, Tony Arcieri wrote:

> On Mon, Nov 9, 2009 at 11:15 AM, TonyMc <afmcc@...> wrote:
>
>> Tony Arcieri <tony@...> writes:
>>
>>> I still find this most appropriate:
>>
>> OK, that gets you killfiled. Getting ruby wrong is not so bad, you
>> just
>> need to learn from the other posts in this thread. Getting real life
>> wrong is another, and much more serious.
>>
>
> Psst, it's a joke, and a self-deprecating one at that.

I too found it really offensive.

James Edward Gray II

Re: Is it possible to do multiple regex in one operation?

2009-11-09T10:39:45Z

Yes, both ways did working for me, thanks for the inputs. At first I
can't imaging regex does have 'and' or 'or' condition in it. But now I
believe

Really appreciate that
--
Posted via http://www.ruby-forum.com/.

Re: Regexp: getting the first found

2009-11-09T10:35:21Z

Ralph Shnelvar wrote:

> Ahmad,
>
> Newbie here so take what I have to say with a grain of salt.
>
> Your pattern is "greedy". To turn it into a lazy pattern add a
> question mark thusly ...
>
> /<<(.*)\/Filter(.*?)>>/
>
> (untested)
>
> Ralph
>

Thanks for the reply.

Basically that's what I need. Thanks for pointing me towards new options
like "greedy". Because of that, I've been able to find new Ruby regex
reference like
http://www.tutorialspoint.com/ruby/ruby_regular_expressions.htm

Really appreciate that, thanks

--
Posted via http://www.ruby-forum.com/.