Mike Beckerle created DAFFODIL-2438:
---------------------------------------
Summary: fn:count with path argument that includes current node -
to become runtime SDE
Key: DAFFODIL-2438
URL: https://issues.apache.org/jira/browse/DAFFODIL-2438
Project: Daffodil
Issue Type: Bug
Components: Back End
Affects Versions: 3.0.0
Reporter: Mike Beckerle
The fn:count, fn:exists, fn:exactly-one, fn:empty functions take a path
expression.
The precise meaning of these is not (yet) defined by the DFDL spec if the
argument is a path that leads to an enclosing element where the expression
resides.
Ex: fn:count(../..) when parsing? It is unclear what this means, and it is
problematic if this relative path is to an enclosing array that contains
elements where this expression is being evaluated at parse time, because
success of the expression determines the count. This is inherently circular, or
overly-constrains implementations to an iterative sequential parse algorithm.
The DFDL Workgroup has discussed clarification of this behavior, and the very
likely result is that use of an argument path (relative or absolute) that
refers to an enclosing element will be defined to be a runtime SDE.
Step 1 however, is to scan existing test suite and known DFDL schemas used with
Daffodil, and to find any such usage. It is expected any such usage can be
revised so as not to depend on this undefined DFDL behavior.
All 4 functions: fn:count, fn:exists, fn:exactly-one, and fn:empty must be
considered.
Then, detection and issuing of this runtime SDE should be implemented, and
negative tests that cause this error added to Daffodil.
--
This message was sent by Atlassian Jira
(v8.3.4#803005)
