Re: [xsl] Lookup (?)

[David Carlisle <davidc@xxxxxxxxx>]

Mike
> evaluate() is easy for an interpreter, but less easy for a compiler, because
> the XPath expression isn't known until run-time, which means that not only
> the XPath parser but also the context (symbol tables, functions, in-scope
> namespaces, base URI) all need to be available at run-time.

But it's very hard for a library like EXSLT to wrap up different
evaluate functions from different namespaces to offer a consistent
interface to the user if the underlying implementations differ on the
edge cases like variable refs that you mentioned. So having a standard,
but optional, specification as part of the standard would be a big win.

Also of course the above issues with compilation are all good reasons
why it is better to add general functionality through higher order
functions which can be compiled rather than through evaluation
of strings as expressions.

However it seems that functions as objects has also moved to the back
burner for XSLT 2?

David

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