Hi, BaseX creators and users.
I have several questions about XQuery versions:
1. The main documentation page [1] for BaseX 12.0 calls it an XQuery 4.0
processor. The XQuery 4.0 draft specification [2] says in section 5.1, "The
XQuery 4.0 specification does not attempt to define the semantics of a query in
which different modules use different version numbers. One approach is to
process all modules as if they specified version "4.0". Another approach (which
may be appropriate if modules are separately compiled) is to process each
module using its own version number; but it is then implementation defined what
happens if (say) a 3.1 module imports a 4.0 library module that declares a
function with a signature that 3.1 does not recognize." The question is: What
does BaseX do if a 3.0 main module imports a 1.0 library module?
2. That same section 5.1 says, "An XQuery 4.0 processor must accept a module in
which the version number is given as "1.0", "3.0", or "3.1". It is then
implementation defined whether the module is processed using the syntax and
semantics of the XQuery 4.0 specification, or the rules of the relevant earlier
version." What does BaseX do for pre-4.0 queries?
3. For the BaseX versions in the not-too-distant past that called themselves
XQuery 3.1 processors, is the answer to question 2 analogous? (I don't see the
same "processor must accept..." verbiage in the XQuery 3.1 specification [3],
though.)
4. (Not BaseX-specific) If a main module declares version "1.0" and uses a
post-1.0 feature like URI-qualified names, that's a bug in the module, right?
Even if the main module imports a 1.0 module, and even if the processor doesn't
complain about the post-1.0 feature usage?
5. (Not BaseX-specific) The 3.1 and 4.0 (draft) specifications explain the
version declaration in terms of intent ("intent that the module be processed by
an XQuery [...] processor"), which is a different criterion compared to stating
the *minimum* XQuery version that would work for that module. If anyone on this
list uses the "minimum" interpretation in practice, do you have any tips for
efficiently determining the minimum required XQuery version for each module in
a set of modules?
The background behind my questions involves an XSpec test for an XQuery module,
where the test gets compiled to a main module that imports the module you are
testing. The main module uses features from 3.0, so I'm trying to determine the
extent to which someone can test a 1.0 module using XSpec.
Thanks,
Amanda
References:
[1] https://docs.basex.org/main/Main_Page
[2]
https://qt4cg.org/specifications/xquery-40/xquery-40.html#id-version-declaration[3]
https://www.w3.org/TR/xquery-31/#id-version-declaration
