Re: variable incrementing in XSLT -- XSLT spec

> Myself and many of us
> fell that it a major handicap in writing programs
> easily in XSLT.

Side effect free programming is not unique to XSLT, it is a long
established programming paradigm, designed to make things easier and
more natural for people. It allows many optimisation strategies that are
not available in imperative programming languages as code may be
re-written and re-arranged by the optimiser with much more freedom.

the use of "variable" in functional languages such as XSLT matches the
use of the word in mathematics (where it originates). there is nothing
at all natural in variables that change their value, that was an
introduction in imperative programming languages which (due to
limitations at the time) are designed to more closely model the machine
implementation than the natural specification of a problem.

> If there is a feature of full scale variables in XSLT, it
> would make programming really easy.

Not at all. If for example you could set a variable in one template and
use its value in another, it would constrain the processor to evaluate
templates in a specific order, which is not the case now, evaluation
might be in any order, or parallelised across different threads, the
fact that each template only returns a single result (like a
mathematical function0 not change the state of arbitrary number of otehr
variables makes this much easier to understand.
 
David

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