NAME

       Lintian::Data::JoinedLines - Lintian interface to query lists of keywords

SYNOPSIS

           my $keyword;
           my $list = Lintian::Data::JoinedLines->new('type');
           if ($list->recognizes($keyword)) {
               # do something ...
           }
           my $hash = Lintian::Data::JoinedLines->new('another-type', qr{\s++});
           if ($hash->value($keyword) > 1) {
               # do something ...
           }
           if ($list->value($keyword) > 1) {
               # do something ...
           }
           my @keywords = $list->all;
           if ($list->matches_any($keyword)) {
               # do something ...
           }

DESCRIPTION

       Lintian::Data::JoinedLines provides a way of loading a list of keywords or key/value pairs
       from a file in the Lintian root and then querying that list.  The lists are stored in the
       data directory of the Lintian root and consist of one keyword or key/value pair per line.
       Blank lines and lines beginning with "#" are ignored.  Leading and trailing whitespace is
       stripped.

       If requested, the lines are split into key/value pairs with a given separator regular
       expression.  Otherwise, keywords are taken verbatim as they are listed in the file and may
       include spaces.

       This module allows lists such as menu sections, doc-base sections, obsolete packages,
       package fields, and so forth to be stored in simple, easily editable files.

       NB: By default Lintian::Data::JoinedLines is lazy and defers loading of the data file
       until it is actually needed.

   Interface for the CODE argument
       This section describes the interface between for the CODE argument for the class method
       new.

       The sub will be called once for each key/pair with three arguments, KEY, VALUE and
       CURVALUE.  The first two are the key/value pair parsed from the data file and CURVALUE is
       current value associated with the key.  CURVALUE will be "undef" the first time the sub is
       called with that KEY argument.

       The sub can then modify VALUE in some way and return the new value for that KEY.  If
       CURVALUE is not "undef", the sub may return "undef" to indicate that the current value
       should still be used.  It is not permissible for the sub to return "undef" if CURVALUE is
       "undef".

       Where Perl semantics allow it, the sub can modify CURVALUE and the changes will be
       reflected in the result.  As an example, if CURVALUE is a hashref, new keys can be
       inserted etc.

INSTANCE METHODS

       dataset
       "keyorder"
       all Returns all keywords listed in the data file as a list in original order.  In a scalar
           context, returns the number of keywords.

       recognizes (KEY)
           Returns true if KEY was listed in the data file represented by this
           Lintian::Data::JoinedLines instance and false otherwise.

       resembles (KEY)
           Returns true if the data file contains a key that is a case-insensitive match to KEY,
           and false otherwise.

       value (KEY)
           Returns the value attached to KEY if it was listed in the data file represented by
           this Lintian::Data::JoinedLines instance and the undefined value otherwise.

       matches_any(KEYWORD[, MODIFIERS])
           Returns true if KEYWORD matches any regular expression listed in the data file. The
           optional MODIFIERS serve as modifiers on all regexes.

       load

FILES

       LINTIAN_INCLUDE_DIR/data
           The files loaded by this module must be located in this directory.  Relative paths
           containing a "/" are permitted, so files may be organized in subdirectories in this
           directory.

           Note that lintian supports multiple LINTIAN_INCLUDE_DIRs.

AUTHOR

       Originally written by Russ Allbery <rra@debian.org> for Lintian.

SEE ALSO

       lintian(1), <https://lintian.debian.org/manual/section-2.6.html>