Ultimately, an XML parser will find some plain text as the content of a simpleType, which will need to be parsed. We use a TextParser, because values of simpleTypes can also be given elsewhere, e.g. as attribute values in an XSD definition, e.g. to restrict the permissible values of the simpleType. Such restrictions are therefore implemented as layered parsers.

Single-precision floating point numbers. It is desirable that this type be at least equal in range and precision to the IEEE single-precision type.

Double-precision floating point numbers. It is desirable that this type be at least equal in range and precision to the IEEE double-precision type.

A QName is a (possibly) qualified name, in the sense of XML namespaces.

Arbitrary-precision integers.

A fixed-precision integer type with at least the range [-2^29 .. 2^29-1]. The exact range for a given implementation can be determined by using minBound and maxBound from the Bounded class.