The eXtensible Programming Script (XPS) serves in a similarly simple yet flexible manner in the area of processing. It has a simple design, yet permitting rich sets of function libraries to be built, both natively and as scripted functions. It is a scripting language that comes naturally with lots of flexibilities, yet provides highly stable data conversions with good performance not normally associated with scripting languages.

Try converting a XML document into binary format, such as a visual bitmap whose content is determined by a received XML file. Or try converting a XML document into an email if certain tag attribute has value "email", into a formatted text file if the same tag attribute has value "text", and prompt the user what to do if it has other values.

attribute = Node@"convert_to";
if (attribute == "email") {
  /* Convert XML Node to 
     email format */
}
else if (attribute == "text") {
  /* Convert XML Node to 
     text format */
}
else {
  print("What should I do (", 
    attribute, ")? ");
  cmd = GetLine();
  /* Do according to cmd's value */
}

If you think this is a rough outline of the conversion example above, incidentally, this is also runnable by XPS; there is no easy and consistent way to do the same in XSLT/ XPath. Take a look at our extensive examples for more illustration of XPS features.

XPS complements XML transformation technologies such as XSLT/ XPath to address non-linear conversions, such as structured from/to unstructured data formats, XML-to-binary (and reverse) conversions, conditional conversions, conversion coupled with action triggering, etc. Being an active transformation language driving XML data conversions instead of trying to use passive XML data to push itself through functional transformations, a great deal of flexibility and conceptual simplification can be achieved. Our XPS design lays a firm foundation for greater functionalities to come.