I suspect that most of the people discussing liberal XML parsing today are unaware that Tim Bray was the singular force behind the
fail on first error behavior of XML. Virtually everyone in the XML working group disagreed with him, and many people pleaded for a sane method of error recovery, or at least the application-specific option to provide error recovery that was suitable for the application. (XML is uniquely suited for such error-tolerant applications. Because it is text-based and has so much redundant information, like verbose end tags, it provides easier re-entry points to recover after a parsing error, unlike most binary formats.)
In the end, Tim basically said
there are two camps here, they both have good points, we aren’t going to convince each other on this one and then proceeded to compromise by doing it his way. Seven years later, we are still paying the price for his dogmatic draconianism.
Update: Tim agrees with the following timeline but disagrees with my conclusion. I would tend to believe him, since he was, you know, there. But we agree on my fundamental point: XML’s error handling has always been controversial, and lots of smart people disagreed with it from the beginning for lots of good reasons.
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