NAME

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

SYNOPSIS

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

DESCRIPTION

       Lintian::Data 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 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.

CLASS METHODS

       new(TYPE [,SEPARATOR[, CODE]])
           Creates  a  new Lintian::Data object for the given TYPE.  TYPE is a partial path relative to the data
           directory and should correspond to a file in that directory.  The  contents  of  that  file  will  be
           loaded  into  memory  and  returned  as  part of the newly created object.  On error, new() throws an
           exception.

           If SEPARATOR is given, it will be used as a regular expression for splitting the lines into key/value
           pairs.

           If CODE is also given, it is assumed to be a sub that will pre-process the key/value pairs.  See  the
           "Interface for the CODE argument" above.

           A  given  file  will  only be loaded once.  If new() is called again with the same TYPE argument, the
           data previously loaded will be reused, avoiding multiple file reads.

       set_vendor(PROFILE)
           Specifies vendor profile.  It must be set before the first data file is loaded.

INSTANCE METHODS

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

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

       value(KEYWORD)
           Returns the value attached to KEYWORD if  it  was  listed  in  the  data  file  represented  by  this
           Lintian::Data  instance and the undefined value otherwise. If SEPARATOR was not given, the value will
           '1'.

DIAGNOSTICS

       no data type specified
           new() was called without a TYPE argument.

       unknown data type %s
           The TYPE argument to new() did not correspond to a file in the data directory of the Lintian root.

       undefined value for %s (type: %s)
           The CODE argument return undef for the KEY and no previous value for that KEY was available.

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>

Lintian v2.5.81ubuntu1                             2018-04-08                                   Lintian::Data(3)