Name
xs:whiteSpace — Facet to define whitespace behavior.
Synopsis
<xs:whiteSpace
fixed = xs:boolean : “false”
id = xs:ID
value = ( “preserve” | “replace” | “collapse” )
{any attributes with non-schema namespace}
>
Content: (xs:annotation?)
</xs:whiteSpace>
May be included in: xs:restriction (simple type), xs:restriction (simple content)
May be used as facet for:xs:ENTITIES, xs:ENTITY, xs:ID, xs:IDREF, xs:IDREFS, xs:language, xs:Name, xs:NCName, xs:NMTOKEN, xs:NMTOKENS, xs:normalizedString, xs:string, xs:token
Description
This facet defines the treatment to perform on whitespace—i.e.,
#x20 (space), #x9 (tab),
#xA (linefeed), and #xD
(carriage return)—during the transformation between the lexical
and value spaces.
Its values are preserve (whitespace characters are
kept unchanged), replace (all instances of
whitespace are replaced with a space), and
collapse (leading and trailing whitespace is
removed and all the other sequences of contiguous whitespace are
replaced by a single space).
Restrictions
This is the only facet (or feature of W3C XML Schema) that interacts with the canonicalization transformation.
It is not possible to “relax” the
whitespace behavior during a restriction: if a datatype has a
whitespace set as preserve, its derived datatypes
can have any whitespace behavior, but if its whitespace is set as
replace, its derived datatypes can only have
whitespace equal to replace or
collapse. If its whitespace is equal to
collapse, all its derived datatypes must have the
same behavior.
This limitation is somewhat paradoxical since it allows the actual expansion of the lexical space of a datatype during a derivation by restriction.