VOTABLE::TD - VOTABLE TD XML element class
use VOTABLE::TD;
This class implements the TD
element from the VOTABLE
DTD. This
element is used to store the contents of a single table cell, and is
analogous to the TD
element in HTML.
The TD
element is a Tier 0 element, and is described by the
following excerpt from the VOTABLE
1.0 DTD:
<!ELEMENT TD (#PCDATA)> <!ATTLIST TD ref IDREF #IMPLIED >
new($str_or_ref, %options)
Create a new VOTABLE::TD
object, and return a reference to it. If
the first argument ($str_or_ref
) is a string, it is used as the
initial PCDATA
content of the TD
element. If the first argument
is a reference to a XML::DOM::Element
object, that object is used
to initialize the new TD
element (implicitly assuming that the
XML::DOM::Element
object contains a valid TD
element). The
%options
hash is used to set the attributes of the new element. If
the first argument is missing or undefined, or an empty string, create
and return an empty VOTABLE::TD
object. Return undef
if an error
occurs.
get
Return a string containing the PCDATA
content of the TD
element. Return undef
if the element has no PCDATA
content, or
an error occurs.
set($str)
Set the PCDATA
content of the TD
element to the specified
string. Return the string on success, or undef
if an error occurs.
_
') are for
internal use only, and should not be used outside of the VOTABLE
class hierarchy.
get_XXX
and set_XXX
accessors for attributes
and elements are derived directly from the names of the attributes or
elements. Attribute and element names containing embedded hyphens
('-
') use accessors where the hyphen is mapped to an underscore
('_
') in the name of the accessor method. This is a necessity,
since the hyphen is not a valid name character in Perl.
VOTABLE::TD
object always has an underlying XML::DOM::Element
object. As long as the internal structure is manipulated only by the
publicly-available methods, this should be an adequate assumption. If
a method detects an aberrant case, a warning message is printed (using
the Carp::carp
subroutine), and the method fails.
XML::DOM
methods always
succeed. If a method detects an aberrant case, a warning message is
printed (using the Carp::carp
subroutine), and the method fails.
set_XXX
accessors do not perform validation of the
new attribute values. The exceptions are the accessors for attributes
with enumerated values; the new value is checked against the list of
acceptable values, as defined in the DTD.
VOTABLE
, VOTABLE::TR
Eric Winter, NASA GSFC (elwinter@milkyway.gsfc.nasa.gov)
$Id: TD.pm,v 1.1.1.8 2002/05/21 14:13:49 elwinter Exp $