ruby-talk-google Google Group

Re: semantics of @x v. $x

2009-11-29T21:02:09Z

SC> @xyzzy = 5 defines an instance variable for the global object. That instance
SC> variable is accessible only from the top level. $xyzzy = 5, instead, defines a
SC> global variable, which can be accessed from everywhere.
SC> Here's an example:
SC> @x = 1
SC> $y = 2
SC> class C
SC>
SC> def test

Re: Best way to distribute an app

2009-11-29T20:33:01Z

Hi, thanks for the replies. I know this question is probably asked a
lot, but thanks. What did you mean about baking gems into apps? I
think rawr fits my needs, but I will also check out Capistrano.

Date class method `once` wraps original call in Array. Why?

2009-11-29T19:50:56Z

I'm reading the Pickaxe and on page 391, there is a code listing for
the class method `once` from the Date module in Ruby:
def once(*ids) #:nodoc:
for id in ids
module_eval <<-"end:"
alias_method :__#{id.to_i}__, :#{id.to_s}
private :__#{id.to_i}__
def #{id.to_s}(*args, &block)

Re: Best way to distribute an app

2009-11-29T19:33:12Z

Two main ways: As a gem, or as a git repository.
As a git repository is helpful if by "deploy" you mean "push to a webserver",
in which case, I suggest you look into Capistrano. As a gem is mostly useful
for other developers, but you get all the advantages of a package manager --
dependencies, seamless upgrades, installing/uninstalling handled for you...

Re: What's the new hotness for packaging gems?

2009-11-29T19:26:30Z

Mostly kidding, too, but I have to agree -- the only gems I've actually built
lately have been small enough that I don't see a real advantage to doing it
programmatically. The last time I did, the only real point I saw was getting a
list of files -- only needed when I was letting Github build gems, and

Re: Class variables, instance variables, singleton; Ruby v.

2009-11-29T19:18:43Z

These are separate questions.
In MRI, you can tell how many instances exist by actually counting them. Look
at the documentation for ObjectSpace.
And yes, you can register a destructor -- that's also in ObjectSpace, and it's
called a "finalizer". But remember, Ruby is garbage-collected -- that means

Re: ruby language parser in ruby

2009-11-29T18:47:43Z

Maglev's got one:
[link]
Jason

Re: ruby language parser in ruby

2009-11-29T18:29:51Z

Awww...
I still thought rubinius was going with the pure ruby approach. :(

Re: ruby language parser in ruby

2009-11-29T18:26:30Z

I'm pretty familiar with CFGs and tools like yacc, or at least, I was
some years ago. What bothers me about ruby syntax is that there are a
number of aspects that I'm not sure how to map to a CFG, for example
puts (a).abs
being different from
puts(a).abs
... or,
a = b
+ c
being treated differently to

Re: Just found a round problem

2009-11-29T18:24:08Z

BigDecimal and Rational will do the trick.
Best,

Re: Which server component?

2009-11-29T18:15:49Z

Another option is to use XMPP (aka Jabber). This is asynchronous and
there are a variety of implementations to choose from. If you want
something that scales to tens of thousands of connections, look at
ejabberd. Even though that's written in erlang, you could still sit it
in between a large pool of clients and a server written in ruby +

Re: Just found a round problem

2009-11-29T18:14:39Z

In C i think its 14/15 significant digits and its probably why.
If you want that much precision, find a way to use a bigger float.

Re: Which server component?

2009-11-29T17:55:08Z

In that case it sounds like as if HTTP was not the ideal protocol for
the task. Maybe you should rather follow the other direction and think
about a solution with EventMachine as Brian has sketched. That way you
can also have better control over the protocol overhead - HTTP can be
quite verbose if your messages are really small (say 50 bytes or so):

Re: how to enable debugging on the server?

2009-11-29T17:40:31Z

This is a Rails question. Please take it to the Rails list.
Best,

how to enable debugging on the server?

2009-11-29T17:17:58Z

Wanting to run the script/server in debugger mode, my dialog looked
like this:
ruby script/server --debugger
=> Booting WEBrick
=> Rails 2.3.4 application starting on [link]
You need to install ruby-debug to run the server in debugging mode.
With gems, use 'gem install
OK, so I installed: