[DFDL-WG] String literal syntax for hexBinary ?? - Re: String literals - various usage patterns thereof

[Mike Beckerle]

> ...  But are we all happy that the result of dfdl:property when the
> property value is an expression, is the result of executing that
> expression? How complicated is that going to make implementations?
>

Well, what is the use case for dfdl:property() at all?  One example would
be where there is a choice, and different record formats as the
alternatives of the choice depending on the length or number of occurrences
of some element. So a discriminator expression would refer to
dfdl:property("length",...) for example.

However, I do believe we could drop dfdl:property(....), and just say "use
variables if you want this behavior". E.g., if I have dfdl:length="{....}"
then as the schema author I can always introduce a variable myLen, set its
value to that of the expression, change to dfdl:length="{ $myLen }" and
where I would have used dfdl:property("length", path), instead just
reference the variable as $myLen. I will have to define the variable, and
use newVariableInstance so that the variable goes into and out of scope
appropriately just like a property value does, but this isn't horribly
complex.

...mikeb
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