Each built-in datatype the base URI is the URI of the XML Schema namespace the fragment identifier is the name of the datatype
For example, to address the http://www.w3.org/2001/XMLSchema#int
Additionally, each facet definition element can be uniquely
addressed via a URI constructed as follows:
the base URI is the URI of the XML Schema namespace the fragment identifier is the name of the facet
For example, to address the maxInclusive facet, the URI is:
http://www.w3.org/2001/XMLSchema#maxInclusive
Additionally, each facet usage in a built-in
the base URI is the URI of the XML Schema namespace the fragment identifier is the name of the
For example, to address the usage of the maxInclusive facet in
the definition of int, the URI is:
http://www.w3.org/2001/XMLSchema#int.maxInclusive
The
http://www.w3.org/2001/XMLSchema
To facilitate usage in specifications other than the XML Schema definition language,
such as those that do not want to know anything about aspects of the
XML Schema definition language other than the datatypes, each
http://www.w3.org/2001/XMLSchema-datatypes
Each
The two datatypes at the root of the hierarchy of simple
types are
For further details of
The
It is a consequence of this definition, together with the
definition of the potential
effable
or nameable
The
It is
The
When a new datatype is defined
by
For further details of
The
The
It is
The
When a new datatype is defined
by
The
Processors
Many human languages have writing systems that require
child elements for control of aspects such as bidirectional formatting or
ruby annotation (see
The
It is
Equality for
As noted in
The
It is
The
The
For a decimal datatype whose values do reflect precision, see
The lexical space of decimal is the set of
lexical representations which match the grammar given above, or
(equivalently) the regular expression
(\+|-)?([0-9]+(\.[0-9]*)?|\.[0-9]+)
The mapping from lexical representations to values is the usual
one for decimal numerals; it is given formally in
The
The mapping from values to
The
As explained below, the
Equality and order for Equality is identity, except that 0 = −0 (although
they are not identical) and NaN ≠ NaN
(although NaN is of course identical to itself). 0 and −0 are thus For the basic values, the order relation
on float is the order relation for rational numbers. INF is greater
than all other non-NaN values; −INF is less than all other non-NaN
values. NaN is
Any value
The Schema 1.0 version of this datatype did not differentiate between
0 and −0 and NaN was equal to itself. The changes were
made to make the datatype more closely mirror
The (\+|-)?([0-9]+(\.[0-9]*)?|\.[0-9]+)([Ee](\+|-)?[0-9]+)?
|(\+|-)?INF|NaN
The
Since IEEE allows some variation in rounding of values, processors
conforming to this specification may exhibit some variation in their
The
The Schema 1.0 version of this datatype did not permit rounding
algorithms whose results differed from
The
The only significant differences between float and double are the three defining constants 53 (vs 24), −1074 (vs −149), and 971 (vs 104).
The
As explained below, the
Equality and order for Equality is identity, except that 0 = −0 (although
they are not identical) and NaN ≠ NaN
(although NaN is of course identical to itself). For the basic values, the order relation
on double is the order relation for rational numbers. INF is greater
than all other non-NaN values; −INF is less than all other non-NaN
values. NaN is
Any value
The Schema 1.0 version of this datatype did not differentiate between
0 and −0 and NaN was equal to itself. The changes were
made to make the datatype more closely mirror
The (\+|-)?([0-9]+(\.[0-9]*)?|\.[0-9]+)([Ee](\+|-)?[0-9]+)?
|(\+|-)?INF|NaN
The
Since IEEE allows some variation in rounding of values, processors
conforming to this specification may exhibit some variation in their
The
The Schema 1.0 version of this datatype did not permit rounding
algorithms whose results differed from
The
) is
a
1696-09-01T00:00:00Z 1697-02-01T00:00:00Z 1903-03-01T00:00:00Z 1903-07-01T00:00:00Z
These four values are chosen so as to maximize
the possible differences in results that could occur,
such as the difference when adding P1M and P30D:
1697-02-01T00:00:00Z + P1M < 1697-02-01T00:00:00Z + P30D ,
but
1903-03-01T00:00:00Z + P1M > 1903-03-01T00:00:00Z + P30D ,
so that P1M <> P30D .
If two
Two totally ordered datatypes (
There are many ways to implement
See the conformance notes in
The PnYnMnDTnHnMnS
More precisely, the
Thus, a
The language accepted by the The expression
The expression The expression -?P[0-9]+Y?([0-9]+M)?([0-9]+D)?(T([0-9]+H)?([0-9]+M)?([0-9]+(\.[0-9]+)?S)?)?
The
In version 1.0 of this specification, the
old style
calendar; the two correspond
approximately but not exactly to each other.
In this version of this specification,
two changes are made in order to agree with existing usage.
First,
Note that 1 BCE, 5 BCE, and so on (years 0000, -0004, etc. in the
lexical representation defined here) are leap years in the proleptic
Gregorian calendar used for the date/time datatypes defined here.
Version 1.0 of this specification was unclear about the treatment of
leap years before the common era
The
See the conformance note in
Equality and order are as prescribed
in
Since the order of a
Although
Order and equality are essentially the same for
The lexical representations for Within a Subsequent Alternatively, For example, 2002-10-10T12:00:00−05:00
(noon on 10 October 2002, Central Daylight
Savings Time as well as Eastern Standard Time
in the U.S.) is equal to 2002-10-10T17:00:00Z,
five hours later than 2002-10-10T12:00:00Z. For the most part, this specification adopts the distinction between
Constraint: Day-of-month Values
) given above.
The
The
See the conformance note in
Equality and order are as prescribed in
A calendar (or
The lexical representations for
The
The
The
See the conformance note in
Equality and order are as prescribed in
In version 1.0 of this specification,
The lexical representations for Within a
Constraint: Day-of-month Values
) given above.-?([1-9][0-9]{3,}|0[0-9]{3})-(0[1-9]|1[0-2])-(0[1-9]|[12][0-9]|3[01])(Z|(\+|-)((0[0-9]|1[0-3]):[0-5][0-9]|14:00))?
The
Because month/year combinations in one calendar only rarely correspond to month/year combinations in other calendars, values of this type are not, in general, convertible to simple values corresponding to month/year combinations in other calendars. This type should therefore be used with caution in contexts where conversion to other calendars is desired.
See the conformance note in
Equality and order are as prescribed in
The lexical representations for
-?([1-9][0-9]{3,}|0[0-9]{3})-(0[1-9]|1[0-2])(Z|(\+|-)((0[0-9]|1[0-3]):[0-5][0-9]|14:00))?
The
Because years in one calendar only rarely correspond to years in other calendars, values of this type are not, in general, convertible to simple values corresponding to years in other calendars. This type should therefore be used with caution in contexts where conversion to other calendars is desired.
See the conformance note in
Equality and order are as prescribed in
The lexical representations for
-?([1-9][0-9]{3,}|0[0-9]{3})(Z|(\+|-)((0[0-9]|1[0-3]):[0-5][0-9]|14:00))?
The
This datatype can be used, for example, to record birthdays; an instance of the datatype could be used to say that someone's birthday occurs on the 14th of September every year.
Because day/month combinations in one calendar only rarely correspond to day/month combinations in other calendars, values of this type do not, in general, have any straightforward or intuitive representation in terms of most other calendars. This type should therefore be used with caution in contexts where conversion to other calendars is desired.
The
Equality and order are as prescribed in
In version 1.0 of this specification,
An example that shows the difference from version 1.0 (see
A day is a calendar (or --12-12+13:00 < --12-12+11:00
(just as --12-12+12:00 has always been less than
--12-12+11:00, but in version 1.0
--12-12+13:00 > --12-12+11:00 , since
--12-12+13:00's
The lexical representations for
Within a Constraint: Day-of-month Values
) given above.--(0[1-9]|1[0-2])-(0[1-9]|[12][0-9]|3[01])(Z|(\+|-)((0[0-9]|1[0-3]):[0-5][0-9]|14:00))?
The
Because days in one calendar only rarely
correspond to days in other calendars,
Equality and order are as prescribed in
Examples that may appear anomalous (see ---15 < ---16 , but ---15−13:00 > ---16+13:00 ---15−11:00 = ---16+13:00 ---15−13:00 <> ---16 ,
because ---15−13:00 > ---16+14:00
and ---15−13:00 < 16−14:00
The lexical representations for ---(0[1-9]|[12][0-9]|3[01])(Z|(\+|-)((0[0-9]|1[0-3]):[0-5][0-9]|14:00))?
The
Because months in one calendar only rarely correspond to months in other calendars, values of this type do not, in general, have any straightforward or intuitive representation in terms of most other calendars. This type should therefore be used with caution in contexts where conversion to other calendars is desired.
Equality and order are as prescribed in
The lexical representations for --(0[1-9]|1[0-2])(Z|(\+|-)((0[0-9]|1[0-3]):[0-5][0-9]|14:00))?
The
The
More formally, the
The set recognized by
The
The
The
The a-z, A-Z,
0-9, the plus sign (+), the forward slash (/) and the
equal sign (=), together with
For compatibility with older mail gateways,
The
The ((([A-Za-z0-9+/] ?){4})*(([A-Za-z0-9+/] ?){3}[A-Za-z0-9+/]|([A-Za-z0-9+/] ?){2}[AEIMQUYcgkosw048] ?=|[A-Za-z0-9+/] ?[AQgw] ?= ?=))?
Note that this grammar requires the number of non-whitespace
characters in the
The
The above definition of the
The canonical
That is, the
For some values the
The length of a
lex2 := killwhitespace(lexform)
-- remove whitespace characters
lex3 := strip_equals(lex2)
-- strip padding characters at end
length := floor (length(lex3) * 3 / 4)
-- calculate length
Note on encoding:
The value space of
The
For an
Each URI scheme imposes specialized syntax rules
for URIs in that scheme, including restrictions on the syntax of
allowed fragment identifiers. Because it is impractical for processors
to check that a value is a context-appropriate URI reference,
neither the syntactic constraints defined by the definitions of individual
schemes nor the generic syntactic constraints defined by
Spaces are, in principle, allowed in the
The
The definitions of URI in the current
IETF specifications define certain URIs as equivalent to each other.
Those equivalences are not part of this datatype as defined here:
if two
It is
The mapping from lexical space to value space for a particular
When
The host language, whether XML-based or otherwise,
The mapping between
Because the lexical representations available for
any value of type
Because its current schema
, as instantiated for example
by
The lexical mapping rules for
It is (with one exception) an
The exception is that in the
Because the lexical representations available for any given value
of
The use of
This section gives conceptual definitions for all
[a-zA-Z]{1,8}(-[a-zA-Z0-9]{1,8})*
The regular expression above provides the only normative
constraint on the lexical and value spaces of this type. The
additional constraints imposed on language identifiers by
are to be treated as case insensitive; there
exist conventions for capitalization of some of
Since the
The empty string is not a member of the
One way to define the desired set of possible values is
illustrated by the schema document for the XML namespace
at
It is
For compatibility (see
anySimpleType
For compatibility (see
It is
It is
It is
For compatibility (see
Uniqueness of items validated as
It is
For compatibility (see
Existence of referents for items validated as
anySimpleType
For compatibility (see
Existence of referents for items validated as
It is
The
For compatibility (see
anySimpleType
The
For compatibility (see
The
The
The
The
The
The
The
The
The
The
The
The
The
The always-zero
The lexical space is reduced from that of
The
The
The
The lexical space is reduced from that of
The
The
As a consequence of requiring an explicit time zone offset, the
lexical space of
For details of the
In other words, the lexical space of
The
The
The