An XML identifier (ID) |
This kind of attribute must have a value that is an XML NAME, which can
consist of XML name characters (alphabetical characters, digits, period,
underscore, and hyphen), and cannot start with a digit. Every ID
attribute value in a single document must be unique and provides a way to link or
refer to its element (for example, using the <xref> element). ID attributes are generally named
@id.
|
An identifier (IDREF) |
This kind of attribute must have a value that is the same as some
ID value in the same document. IDREFs appear on
elements that refer to other elements such as <xref>. IDREF attributes are generally named
@rid. Some @rid attributes are of type IDREFS,
which is simply a space-separated list of IDREF values.
|
Text, numbers, or special characters (CDATA) |
These attributes can take any string value at all. If the attribute value is
surrounded by single quotes, then single quotes cannot appear inside; if the
attribute value is surrounded by double quotes, then double quotes cannot appear
inside. In either case, the prohibited character can instead be represented by an
XML character reference such as “'”. XML elements cannot
be placed within attribute values.
|
“xxx-type” attributes |
There are many attributes whose names end
in “-type”. They are generally CDATA attributes as described above.
They are typically assigned tokens as values, containing no spaces. Typically if
there are spaces in the value, they separate multiple independent tokens, all of
which apply. For example, some element might be both of
type “important” and
“normative”, and be given
type “important normative”. In many cases,
the Tag Library gives suggested values for such
attributes. Unless specifically stated otherwise, those values are not the only
values permitted.
|
? |
means that the item is optional (zero or one)
|
* |
means that the item may occur any number of times (zero or more)
|
+ |
means that the item must occur at least once, but may occur any number of
times (one or more)
|
a thick vertical bar on the left of the box |
means that the item is the “document element”: the top-most
element, such as <article> or <book> and is
therefore required.
|
(no symbol) |
means that the item must occur exactly once
|
˜ (a tilde) |
means that the item may have attribute
|
a thick vertical bar on the right of the box |
means that the item is expanded elsewhere (For example, if an element is
permitted in multiple places within a certain parent element, there is little
point in repeating its information many times.
|
Journal Archiving and Interchange Tag Library NISO JATS Draft Version 1.1d2
Version of December 2014