NAME

       Lucy::Search::Query - A specification for a search query.

SYNOPSIS

           # Query is an abstract base class.
           package MyQuery;
           use base qw( Lucy::Search::Query );

           sub make_compiler {
               my ( $self, %args ) = @_;
               my $subordinate = delete $args{subordinate};
               my $compiler = MyCompiler->new( %args, parent => $self );
               $compiler->normalize unless $subordinate;
               return $compiler;
           }

           package MyCompiler;
           use base ( Lucy::Search::Compiler );
           ...

DESCRIPTION

       Query objects are simple containers which contain the minimum information necessary to
       define a search query.

       The most common way to generate Query objects is to feed a search string such as 'foo AND
       bar' to a QueryParser's parse() method, which outputs an abstract syntax tree built up
       from various Query subclasses such as ANDQuery and TermQuery.  However, it is also
       possible to use custom Query objects to build a search specification which cannot be
       easily represented using a search string.

       Subclasses of Query must implement make_compiler(), which is the first step in compiling a
       Query down to a Matcher which can actually match and score documents.

CONSTRUCTORS

   new( [labeled params] )
           my $query = MyQuery->SUPER::new(
               boost => 2.5,
           );

       Abstract constructor.

       •   boost - A scoring multiplier, affecting the Query's relative contribution to each
           document's score.  Typically defaults to 1.0, but subclasses which do not contribute
           to document scores such as NOTQuery and MatchAllQuery default to 0.0 instead.

ABSTRACT METHODS

   make_compiler( [labeled params] )
       Abstract factory method returning a Compiler derived from this Query.

       •   searcher - A Searcher.

       •   boost - A scoring multiplier. Defaults to the Query's own boost.

       •   subordinate - Indicates whether the Query is a subquery (as opposed to a top-level
           query).  If false, the implementation must invoke normalize() on the newly minted
           Compiler object before returning it.

METHODS

   set_boost(boost)
       Set the Query's boost.

   get_boost()
       Get the Query's boost.

INHERITANCE

       Lucy::Search::Query isa Lucy::Object::Obj.