[patrickg]

* Infrastructure (schema support - DTD, Schema, RelaxNG; transformation - XSLT) * No obvious document format (What encoding are the strings? How to escape characters? * Only used to describe predefined object types (boolean, strings, arrays, dictionaries * Hard to ensure the integrity of the data without interpreting the data from the interpreter itself (no external validation)

[rauar]

You know this can be done on top when you have demand for this? I prefer a non-bloated protocol format over XML anytime. How often does the DTD not matter at all ? How often is the encoding fixed by convention ? ...

[patrickg]

I use schemas (in the form of RelaxNG most of the time) almost every time I deal with XML. Together with schematron you can make very complex lint-like scripts to verify your data. Actually I program in XML with a self created programming language (formulated in XML). This together with RelaxNG and a good XML makes it fun writing XML and absolutely (syntax-)error free.