NAME

XML::Easy::Classify - classification of XML-related items

SYNOPSIS

    use XML::Easy::Classify qw(
	is_xml_name check_xml_name
	is_xml_encname check_xml_encname
	is_xml_chardata check_xml_chardata
	is_xml_attributes check_xml_attributes
	is_xml_content_object check_xml_content_object
	is_xml_content_twine check_xml_content_twine
	is_xml_content check_xml_content
	is_xml_element check_xml_element);

    if(is_xml_name($arg)) { ...
    check_xml_name($arg);
    if(is_xml_encname($arg)) { ...
    check_xml_encname($arg);
    if(is_xml_chardata($arg)) { ...
    check_xml_chardata($arg);

    if(is_xml_attributes($arg)) { ...
    check_xml_attributes($arg);

    if(is_xml_content_object($arg)) { ...
    check_xml_content_object($arg);
    if(is_xml_content_twine($arg)) { ...
    check_xml_content_twine($arg);
    if(is_xml_content($arg)) { ...
    check_xml_content($arg);

    if(is_xml_element($arg)) { ...
    check_xml_element($arg);

DESCRIPTION

This module provides various type-testing functions, relating to data types used in the XML::Easy ensemble. These are mainly intended to be used to enforce validity of data being processed by XML-related functions.

There are two flavours of function in this module. Functions of the first flavour only provide type classification, to allow code to discriminate between argument types. Functions of the second flavour package up the most common type of type discrimination: checking that an argument is of an expected type. The functions come in matched pairs.

FUNCTIONS

Each of these functions takes one scalar argument (ARG) to be tested. Any scalar value is acceptable for the argument to be tested. Each is_ function returns a simple truth value result, which is true iff ARG is of the type being checked for. Each check_ function will return normally if the argument is of the type being checked for, or will die if it is not.

is_xml_name(ARG)
check_xml_name(ARG)

Check whether ARG is a plain string satisfying the XML name syntax. (Such names are used to identify element types, attributes, entities, and other things in XML.)

is_xml_encname(ARG)
check_xml_encname(ARG)

Check whether ARG is a plain string satisfying the XML character encoding name syntax.

is_xml_chardata(ARG)
check_xml_chardata(ARG)

Check whether ARG is a plain string consisting of a sequence of characters that are acceptable to XML. Such a string is valid as data in an XML element (where it may be intermingled with subelements) or as the value of an element attribute.

is_xml_attributes(ARG)
check_xml_attributes(ARG)

Check whether ARG is a reference to a hash that is well-formed as an XML element attribute set. To be well-formed, each key in the hash must be an XML name string, and each value must be an XML character data string.

is_xml_content_object(ARG)
check_xml_content_object(ARG)

Check whether ARG is a reference to an XML::Easy::Content object, and thus represents a chunk of XML content.

is_xml_content_twine(ARG)
check_xml_content_twine(ARG)

Check whether ARG is a reference to a twine array (see "Twine" in XML::Easy::NodeBasics), and thus represents a chunk of XML content.

is_xml_content_array(ARG)

Deprecated alias for "is_xml_content_twine".

is_xml_content(ARG)
check_xml_content(ARG)

Check whether ARG is a reference to either an XML::Easy::Content object or a twine array (see "Twine" in XML::Easy::NodeBasics), and thus represents a chunk of XML content.

is_xml_element(ARG)
check_xml_element(ARG)

Check whether ARG is a reference to an XML::Easy::Element object, and thus represents an XML element.

SEE ALSO

Params::Classify, XML::Easy::NodeBasics

AUTHOR

Andrew Main (Zefram) <zefram@fysh.org>

COPYRIGHT

Copyright (C) 2009, 2010, 2011, 2017 Andrew Main (Zefram) <zefram@fysh.org>

LICENSE

This module is free software; you can redistribute it and/or modify it under the same terms as Perl itself.