NAME

       SGML::Parser::OpenSP::Tools - Tools to process OpenSP output

DESCRIPTION

       Routines to post-process OpenSP event data.

UTILITY FUNCTIONS

       specified_attribute($attribute)
           specified_attribute returns a true value if the attribute is of type "cdata" or
           "tokenized" and has its "Defaulted" property set to "specified". For example

             sub start_element
             {
               my $self = shift;
               my $elem = shift;
               my @spec = grep specified_attribute($_),
                               values %{$elem->{Attributes}};

               # @spec contains all explicitly specified attributes
             }

       defaulted_attribute($attribute)
           defaulted_attribute returns a true value if the attribute is of type "cdata" or
           "tokenized" and has its "Defaulted" property set to something but "specified". For all
           attributes, the following always holds true,

             !defined(attribute_value($_)) or
             defaulted_attribute($_) or
             specified_attribute($_)

           since only defaulted and specified attributes can have a value.

       value_attribute($attribute)
           Returns true if the value can have a value, i.e., it is either specified or defaulted.

       attribute_value($attribute)
           attribute_value returns a textual representation of the value of an attribute as
           reported to a "start_element" handler or "undef" if no value is available.

       split_message($message, $filename, $open_ent, $error_num, $open_elem)
           split_message splits an OpenSP error message into its components, the error or warning
           message, an optional auxiliary message that provides additional information about the
           error, like the first occurence of an ID in case of duplicate IDs in a document, each
           accompanied by line and column numbers relevant to the message, and depending on the
           parser configuration the open entities for the message, the error number of the
           message and a list of the current open elements.

           It returns a hash reference like

             # this is always present
             primary_message =>
             {
               Number       => 141,       # only if $p->show_error_numbers(1)
               Module       => 554521624, # only if $p->show_error_numbers(1)
               ColumnNumber => 9,
               LineNumber   => 12,
               Severity     => 'E',
               Text         => 'ID "a" already defined'
             },

             # only some messages have an aux_message
             aux_message =>
             {
               ColumnNumber => 9,
               LineNumber   => 11,
               Text         => 'ID "a" first defined here'
             },

             # iff $p->show_open_elements(1) and there are open elements
             open_elements => 'html body[1] (p[1])',

             # iff $p->show_open_entities(1) and there are open entities
             # other than the document, but the document will be reported
             # if the error is in some other entity
             open_entities => [
             {
               ColumnNumber => 55,
               FileName     => 'example.xhtml',
               EntityName   => 'html',
               LineNumber   => 2
             }, ... ],

           This would typically be used like

             sub error
             {
               my $self = shift;
               my $erro = shift;
               my $mess = $erro->{Message};

               # parser is the SGML::Parser::OpenSP
               # object stored in the handler object
               my $loca = $self->{parser}->get_location;
               my $name = $loca->{FileName};

               my $splt = split_message($mess, $name,
                                        $self->{parser}->show_open_entities,
                                        $self->{parser}->show_error_numbers,
                                        $self->{parser}->show_open_elements);

               # ...
             }

           A more convenient way to access this function is provided by the
           "SGML::Parser::OpenSP" module which you can use like

             sub error
             {
               my $self = shift;
               my $erro = shift;

               my $mess = $self->{parser}->split_message($erro);

               # relevant data is now $mess and $erro->{Severity}
               # of which the latter provides more detailed information
               # than $mess->{primary_message}->{Severity}, see the
               # SGML::Parser::OpenSP documentation for details
             }

       split_pi($data)
           split_pi splits the data of a processing instructions at the first white space
           character into two components where white space character is defined in the
           $WHITESPACE package variable, qr/[\x20\x09\x0d\x0a]/ by default. It returns "undef" if
           there is no data to split.

             sub pi
             {
               my $self = shift;
               my $proc = shift;

               my ($target, $data) = split_pi($proc->{Data});

               # ...
             }

AUTHOR / COPYRIGHT / LICENSE

         Copyright (c) 2006-2008 Bjoern Hoehrmann <bjoern@hoehrmann.de>.
         This module is licensed under the same terms as Perl itself.