Personally, I'd like to see this comment explained more. "non-idiomatic"? I believe that tye and tilly (among many others) have made case that callbacks are not "non-idiomatic" in Perl. Perl is as functional as it is procedural (and heck of a lot more of both than it is OO). I would posit that the venerable Mr. Bray is less comfortable with functional logic than he is will XML. *

Writing in callbacks is counter-intuitive, yes. But, only if you're attempting to shoe-horn callbacks into a procedural or OO model. If you're not, then I would say that callbacks are extremely intuitive. I certainly have found them so and I have only encountered callbacks and lambda-functions in Perl (never having programmed in LISP, Haskell, Scheme, or the like).

So I think the key first step is to make XML stream processing idiomatic in as many programming languages as possible.

What would Mr. Bray consider stream processing to be, other than callbacks? Another response to this node says that while (<STDIN>) { ... } is interchangeable with callbacks, and I agree completely.

Are the callback interfaces out there complete? Maybe not. But, equating that with the statement that callback interfaces are "non-idiomatic and awkward" is a logical fallacy.

And, while I'm up on this soapbox, I would say that XML is not a panacea. It does lend itself to marking up data. Heck, that's all a "markup language" is meant to do, text being data. But, it most definitely is not a replacement for a RDBMS, and I find it used as such way too often. Personally, I find it wonderful as a layout specifier in PDF::Template. It's also a really neat data transport mechanism, having the qualities that it's flat text and in an agreed-upon format with parsers and writers readily available.

(* - Yes, I understand that speaking ill of a "Great One" is poor form, but I find little benefit in assuming that someone has more skill than they may have.)

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We are the carpenters and bricklayers of the Information Age.

Don't go borrowing trouble. For programmers, this means Worry only about what you need to implement.

Please remember that I'm crufty and crochety. All opinions are purely mine and all code is untested, unless otherwise specified.