Re: [PHP-XML-DEV] Re: [PHP-DEV] Replacing expat with libxml

On Sun, 2003-04-27 at 20:12, Zeev Suraski wrote:
> At 15:32 27/04/2003, Sterling Hughes wrote:
> >Hi,
> >
> >After some discussions with various people at the PHP-Con, I decided it
> >was important that we (at least) have libxml integrated with PHP by
> >PHP5.  When it comes to XML processing, expat is a legacy library and it
> >doesn't support nearly what is required for processing XML by todays
> >standards.
> 
> I'm also somewhat worried about the downwards compatibility with 
> expat.  Given the relatively wide scope of XML parsing, it'd be a small 
> miracle if libxml can replace expat without breaking anybody's scripts, 
> because of whatever quirks libxml and/or expat have.  I suggest we keep 
> expat bundled as well, the price of bundling it is negligible.
> 

I think we certainly need to test, test and retest.  Find as many
available XML code out there, and make sure it works. But the whole
point of standards, is to be, well, standard.  It means you can change
the underlying library, and the interface doesn't change.  The XML error
codes are not a serious BC break (they won't be undefined, they'll just
be unused, this means that only if you require an error condition, will
your code be affected).

I see no reason why both libraries should be bundled, on the <1% chance
that bc is broken.  We can test it on a large majority of PHP scripts,
and if there are unfixable breaks, this can be reconsidered. Currently,
PEAR works and installs, namespaces work, elements, attributes,
encodings all work and validate (no changes from original code, works
the same in both versions of php.)

-Sterling
-- 
"Reductionists like to take things apart.  The rest of us are 
 just trying to get it together." 
    - Larry Wall, Programming Perl, 3rd Edition