From pfeil at amazon.com  Fri Dec 16 01:24:51 2005
From: pfeil at amazon.com (Greg Pfeil)
Date: Thu, 15 Dec 2005 17:24:51 -0800
Subject: [cl-containers-devel] Using CL-Containers
Message-ID: <BFC75763.13131%pfeil@amazon.com>

So, as of today, I'm successfully using CL-Containers at work. Huzzah!

A few things I've noticed:

1. I couldn't find an easy way to get an element count for a container.

2. I couldn't find an intuitive way to reverse a list. My solution was:

    (make-container 'list-container
                    :initial-contents prev-cont)

which reverses the list for me. I would have assumed that :initial-contents
maintains the same order, but that's not the case.

3. I think I misunderstand the way item-at works. I figured that with an
ASSOCIATIVE-CONTAINER, I could access nested hashes like:

    (item-at container "Config" "server" "port") => 80

But what happens is:

    (item-at container "Config" "---" "---") => #<ASSOCIATIVE-CONTAINER ...>

basically ignoring any keys after the first. Requiring something like:

    (item-at (item-at (item-at container "Config") "server") "port") => 80

Overall, I'm pretty happy with the library, but was hoping that these things
could be addressed. Am I looking for the wrong thing? Is this
not-yet-implemented functionality?

Thanks a lot for this. I'm re-writing a lot of code to use CL-Containers
now.

Oh, one other thing ... Will the new Moptilities require a new
CL-Containers, or is the interface basically unchanged?




From gwking at metabang.com  Fri Dec 16 15:05:34 2005
From: gwking at metabang.com (Gary King)
Date: Fri, 16 Dec 2005 10:05:34 -0500
Subject: [cl-containers-devel] Using CL-Containers
In-Reply-To: <BFC75763.13131%pfeil@amazon.com>
References: <BFC75763.13131%pfeil@amazon.com>
Message-ID: <DD76727A-D765-4D09-87A3-3B464EC376EE@metabang.com>

Hi Greg,

On Dec 15, 2005, at 8:24 PM, Greg Pfeil wrote:

> So, as of today, I'm successfully using CL-Containers at work. Huzzah!

Great!


> 1. I couldn't find an easy way to get an element count for a  
> container.

The generic function #'size returns the element-count for any  
container (someday there will be documentation <sad face>.
> 2. I couldn't find an intuitive way to reverse a list. My solution  
> was:

Why would anyone ever want to reverse a list... <grin>. There isn't  
one. Actually, it is sort of strange but I've never wanted to reverse  
a container in all the time I've been working with them. It is,  
however, a function that ought to be there.  I'll look into adding  
reverse-container for subclasses of ordered containers.

> 3. I think I misunderstand the way item-at works. I figured that  
> with an
> ASSOCIATIVE-CONTAINER, I could access nested hashes like:
>
>     (item-at container "Config" "server" "port") => 80

This actually should work. I'll investigate.

> Thanks a lot for this. I'm re-writing a lot of code to use CL- 
> Containers
> now.

I'm glad to hear it.

> Oh, one other thing ... Will the new Moptilities require a new
> CL-Containers, or is the interface basically unchanged?

No. There will be some changes in the cl-containers code (so it will  
need to be refreshed and maybe recompiled) but the interface will  
stay the same.

-- 
Gary Warren King
metabang.com
http://www.metabang.com/


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From pfeil at amazon.com  Fri Dec 16 20:53:52 2005
From: pfeil at amazon.com (Greg Pfeil)
Date: Fri, 16 Dec 2005 12:53:52 -0800
Subject: [cl-containers-devel] Using CL-Containers
In-Reply-To: <DD76727A-D765-4D09-87A3-3B464EC376EE@metabang.com>
Message-ID: <BFC86960.131D6%pfeil@amazon.com>

On 12/16/05 7:05 AM, "Gary King" <gwking at metabang.com> wrote:

> On Dec 15, 2005, at 8:24 PM, Greg Pfeil wrote:
> 
>> 1. I couldn't find an easy way to get an element count for a
>> container.
> 
> The generic function #'size returns the element-count for any
> container (someday there will be documentation <sad face>.

Jeez, I should have just tried this, rather than looking for it. Thanks.
However ... You use 'count' in other places (eg, ELEMENT-COUNTS,
COUNT-ELEMENTS) to mean the number of elements, and you have TOTAL-SIZE
which looks like it might be related to the in-memory size, rather than the
number of elements?

>> 2. I couldn't find an intuitive way to reverse a list. My solution
>> was:
> 
> Why would anyone ever want to reverse a list... <grin>. There isn't
> one. Actually, it is sort of strange but I've never wanted to reverse
> a container in all the time I've been working with them. It is,
> however, a function that ought to be there.  I'll look into adding
> reverse-container for subclasses of ordered containers.

Well, in this case, I'm calling INSERT-ITEM repeatedly, then reversing
afterward. Just because I'm used to doing that instead of appending
individual elements.

>> 3. I think I misunderstand the way item-at works. I figured that
>> with an
>> ASSOCIATIVE-CONTAINER, I could access nested hashes like:
>> 
>>     (item-at container "Config" "server" "port") => 80
> 
> This actually should work. I'll investigate.

I just tried this tiny example:

    (defparameter conf
                  (make-container 'associative-container :test #'equal))
    (item-at! conf "val" "foo" "bar" "baz")
    (item-at conf "foo" "bar" "baz")

And it worked exactly as you said. Here's my guess: I'm not really using a
single ASSOCIATIVE-CONTAINER. I keep doing:

    (let (new-hash (make-container 'associative-container :test #'equal))
      (item-at! new-hash "val" "bar")
      (item-at! primary-hash new-hash "foo"))
    (item-at primary-hash "foo" "bar")

So, it doesn't merge the different containers together. So, I can fix my
code to not work this way. That's not a problem. However, it does still
leave open whether or not this is what you want. I think merging them would
be cool, but you need to be able to do

    (item-at conf "foo" "bar")

And get back an ASSOCIATIVE-CONTAINER, and also do

    (item-at conf "foo" "bar" "baz")

To get back the value. Right now you can only do one or the other, the
former if you insert a separate container, the latter if you build it all in
one container. Also, being able to mix ASSOCIATIVE- and INDEXED- container
types would be awesome. Like:

    (item-at conf "foo" "bar" 2 "zoob")

Akin to (in Perl):

    $conf->{foo}{bar}[2]{zoob}

So yeah. Thanks again. I'll work on rearranging my code a bit.