XProc namespaces

XProc has three namespaces:

"http://www.w3.org/ns/xproc"

This namespace is used most frequently because it contains the entire vocabulary of the language. By convention a “p:“ is used as prefix.

"http://www.w3.org/ns/xproc-step"

Here, a “c:“ is used as prefix. The namespace describes documents which can be input as well as output of various standard or optional steps.

"http://www.w3.org/ns/xproc-error"

This namespace is used for error outputs. The prefix preset by convention is “err:“.