Re: [Boost-users] [fusion] sequence conversion

From: Istvan Buki (buki.istvan_at_[hidden])
Date: 2008-07-19 12:16:53

Hi,

On Sat, Jul 19, 2008 at 3:13 PM, Joel de Guzman <joel_at_[hidden]>
wrote:

> Zeljko Vrba wrote:
>
>> On Fri, Jul 18, 2008 at 10:17:28PM +0200, Istvan Buki wrote:
>>
>>> Steven,
>>>
>>> your solution is exactly what I needed.
>>> My only dream is to be able to manipulate these concepts as well as you
>>> do.
>>>
>>>  Just out of curiosity -- could you please describe your real underlying
>> problem that made you turn to fusion?  The fusion manual is severely
>> lacking in motivation, esp. when it comes to transformations, so any
>>
>
> What do you mean by transformations?
>
>  examples from the real world are welcome.
>>
>> Or, to reformulate the question: which imminent problem at hand do you
>> have
>> and what is the advantage of solving it by fusion instead of by
>> "traditional"
>> means?
>>
>
> Again, please define "traditional means".
>
>  Thank you.
>>
>> (PS: I have some experience with functional languages such as ML and I
>> *do*
>> know what *tuples* are useful for.. but the rest? [and the 'rest' does not
>> even cover ML-style pattern matching])
>>
>
> What is "rest" and why should fusion cover ML-style pattern matching?
>
> Anyway...
>
> If anyone can suggest a motivating example and how to improve the
> docs, I'd appreciate it a lot.
>
>
I do not know for sure if what I'm working on is a good example for using
fusion.
It started as an experiment to learn more about some of the boost libraries.
The application is a very small ETL tool which allows me to load and save
data from CSV files or database tables. Each record is represented by a
fusion map. Between the load and save components I can insert all kind of
filters to transform the data contained in the map.

The question I asked the other day was more specifically related to the
database component that is using the SOCI library which is making use of
fusion vectors to represent the rows of a table. I needed a way to copy the
data contained in a fusion map into a fusion vector before storing it into
the database.

One of the next component I will probably develop is a something to load XML
messages from a file.
I'm not yet decided how I'll represent the XML data in the application. I
saw that there is a fusion tree in the ext directory but I'm not sure how
stable it is. Steven already helped me a while ago to understand how to work
with nested fusion maps. If you have suggestions regarding this subject I
would like to hear them.

I hope this can help you.

Istvan Buki