Re: [Boost-users] spirit and xml

From: Boris Kolpackov (boris_at_[hidden])
Date: 2007-02-12 15:39:35

Hi Abir,

abir basak <abirbasak_at_[hidden]> writes:

>   Now I am looking to use spirit for parsing an specific xml file ( w3c
> inkml file). So my intension is not to have a generic xml parser, rather
> than a specific xml parser (which also have some BNF grammar) . Anyone
> had used spirit for domain specific xml parsing?

Trust me you don't want to go this route. Parsing XML is a lot more
than finding opening and closing tags. To implement a conforming XML
parser you will need to handle namespaces, entity references, CDATA,
etc. This is a lot harder to get right than most people think.

The only time it makes sense to have a domain specific XML parser is
when you have control over all your XML instances and can make sure
that only a subset of XML 1.0 is used. This is normally done for
performance reasons.

>   I believe using spirit will make it faster.

Highly unlikely since most of the XML parsers are hand-coded.

> Also I am interested to
> parse only a portion of the whole document at a time, and generate data
>   from that portion only, rather generating data for whole DOM (The
> files are large, 4-20 MB typically)
> my xml file is something like,
>
> [...]
>
> note that inside <trace> the grammar is a BNF (comma sep float pairs
> mostly)

You can use a SAX2 parser (e.g., Expat or Xerces-C++) to handle XML and
then use Spirit-based parser to handle the data.

hth,
-boris

-- 
Boris Kolpackov
Code Synthesis Tools CC
http://www.codesynthesis.com
Open-Source, Cross-Platform C++ XML Data Binding