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what does "finite-length" mean?

From: Morris Matsa <mmatsa@us.ibm.com>
Date: Tue, 19 Dec 2000 18:27:39 -0500
To: www-xml-schema-comments@w3.org
Message-ID: <OF7307F60D.50F4F455-ON852569BA.0061CB68@somers.hqregion.ibm.com>

The term "finite-length" is used many times in part 2 of the spec, but
never defined.  It seems implied that "finite-length" means "of a length
which is any non-negative integer."  If you look up the mathematical
definition of "finite"
(http://www.dictionary.com/cgi-bin/dict.pl?term=finite) you find many
options which seem to indicate ("1.      Having a positive or negative
numerical value; not zero.") that zero is not included.  This would imply
that lists, strings, decimals, binary values, etc. are not allowed to be
empty.  Furthermore, some types (e.g. IDREFS
http://www.w3.org/TR/xmlschema-2/#IDREFS) specify that the value space is a
finite-length sequence of elements, but the lexical space has no such
constraint (being a "set of whitespace separated tokens").  It would seem
that this term should be used either for both value space and lexical
space, or neither, in the case of a list type.  My question is what the
actual meaning in the spec is for "finite-length" and I suggest that it is
defined in the spec.

A related question:  Lists are a "finite-length" sequence of values. (2.5.1
http://www.w3.org/TR/xmlschema-2/#atomic-vs-list and 3.1
http://www.w3.org/TR/xmlschema-2/#namespaces), alternatively their value
space is composed of "finite" sequences of values (5.1.2
http://www.w3.org/TR/xmlschema-2/#derivation-by-list).  This implies that
there is no difference between a "finite-length sequence" and a "finite
sequence".  Am I correct?  If so, why are they worded differently?
Received on Tuesday, 19 December 2000 18:28:40 GMT

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