begin  quoting Gabriel Sechan as of Tue, Oct 25, 2005 at 05:12:36PM -0500:
[snip]
> Writing a parser for a spec like XML is hard-  thats why most XML parsers 
> are buggy.  Writing a parser for a small domain language is quite easy.  
> Its a simple state machine.  For middle sized languages, you have lex and 
> yacc.
> 
> The hard part of parsing data isn't the parsing-  its dealing with the 
> tokens after its parsed, and designing a good language to begin with.  XML 
> helps neither of those activities.  You still need to deal with the tokens, 
> you still need to design a good schema.  The second one perhaps being the 
> biggest problem-  when you see buggy non-XML parsers, chances are the 
> language spec is too convoluted.  Of course, if they changed it to XML tags 
> it wouldn't be magicly better- you'd still have a convoluter schema, 
> wrapped in tags.
[snip]

What he said!

[snip]
> Yup, because just dumping the doc rather than trying to route around the 
> problem is a great idea.  Nah, I didn't really want all that data.  So 
> whats a few missing bank transactions gonna cost anyway?

Anything that gets used as a file-storage format should be able to
handle corrupted sections.

[snip]
> There's a reason most real world programs are liberal with inputs-  they 
> have to be.  You can't expect the other guy to get his shit right, 
> especially if he's not employed with you.  And failing to the end user is 
> not a good option, not when the error can be routed around.

There's a series of tradeoffs. Low-level needs to be more correct and
strict than high level.
  
 [snip]
> And you could have saved yourself a lot of work in 99% of cases by not 
> using XML, and not having to worry about the nasty gnarly stuff at all.  
> Just write a language that does what you need, no more no less.

I suspect there's a philosophy difference here. Some people find it
easy to invent a new "little language" and are good at it, some people
find it easy but aren't good at it, some people find it hard and want
to find a meta-language that lets them write one language they can 
use everywhere.

-Stewart

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