Base class for a PostList which wraps another PostList. More...

#include <wrapperpostlist.h>

Inheritance diagram for WrapperPostList:

Collaboration diagram for WrapperPostList:

Public Member Functions
	WrapperPostList (PostList *pl_)

	~WrapperPostList ()

Xapian::docid	get_docid () const
	Return the current docid. More...

double	get_weight (Xapian::termcount doclen, Xapian::termcount unique_terms, Xapian::termcount wdfdocmax) const
	Return the weight contribution for the current position. More...

bool	at_end () const
	Return true if the current position is past the last entry in this list. More...

double	recalc_maxweight ()
	Recalculate the upper bound on what get_weight() can return. More...

PositionList *	read_position_list ()
	Read the position list for the term in the current document and return a pointer to it (owned by the PostList). More...

PostList *	next (double w_min)
	Advance the current position to the next document in the postlist. More...

PostList *	skip_to (Xapian::docid, double w_min)
	Skip forward to the specified docid. More...

std::string	get_description () const
	Return a string description of this object. More...

Xapian::termcount	get_wdf () const
	Return the wdf for the document at the current position. More...

Xapian::termcount	count_matching_subqs () const
	Count the number of leaf subqueries which match at the current position. More...

Public Member Functions inherited from Xapian::Internal::PostList
virtual	~PostList ()
	We have virtual methods and want to be able to delete derived classes using a pointer to the base class, so we need a virtual destructor. More...

Xapian::doccount	get_termfreq () const
	Get an estimate of the number of documents this PostList will return. More...

virtual PositionList *	open_position_list () const
	Read the position list for the term in the current document and return a pointer to it (not owned by the PostList). More...

virtual PostList *	check (Xapian::docid did, double w_min, bool &valid)
	Check if the specified docid occurs in this postlist. More...

PostList *	next ()
	Advance the current position to the next document in the postlist. More...

PostList *	skip_to (Xapian::docid did)
	Skip forward to the specified docid. More...

virtual void	gather_position_lists (OrPositionList *orposlist)
	Gather PositionList* objects for a subtree. More...

virtual void	get_docid_range (docid &first, docid &last) const
	Get the bounds on the range of docids this PostList can return. More...

Protected Attributes
PostList *	pl

Protected Attributes inherited from Xapian::Internal::PostList
Xapian::doccount	termfreq
	Estimate of the number of documents this PostList will return. More...

Private Member Functions
void	operator= (const WrapperPostList &)=delete
	Don't allow assignment. More...

	WrapperPostList (const WrapperPostList &)=delete
	Don't allow copying. More...

Additional Inherited Members
Protected Member Functions inherited from Xapian::Internal::PostList
	PostList ()
	Only constructable as a base class for derived classes. More...

Detailed Description

Base class for a PostList which wraps another PostList.

Generally methods are just forwarded to the wrapped PostList. For next() and skip_to(), the return value is also handled, so the wrapped PostList is updated when pruning happens.

Definition at line 32 of file wrapperpostlist.h.

Constructor & Destructor Documentation

◆ WrapperPostList() [1/2]

WrapperPostList::WrapperPostList ( const WrapperPostList & )

privatedelete

Don't allow copying.

◆ WrapperPostList() [2/2]

WrapperPostList::WrapperPostList ( PostList * pl_ )

inlineexplicit

Definition at line 43 of file wrapperpostlist.h.

References Xapian::Internal::PostList::get_termfreq(), pl, and Xapian::Internal::PostList::termfreq.

◆ ~WrapperPostList()

WrapperPostList::~WrapperPostList ( )

inline

Definition at line 47 of file wrapperpostlist.h.

References pl.

Member Function Documentation

◆ at_end()

bool WrapperPostList::at_end ( ) const

virtual

Return true if the current position is past the last entry in this list.

Implements Xapian::Internal::PostList.

Definition at line 40 of file wrapperpostlist.cc.

References Xapian::Internal::PostList::at_end(), and pl.

◆ count_matching_subqs()

Xapian::termcount WrapperPostList::count_matching_subqs ( ) const

virtual

Count the number of leaf subqueries which match at the current position.

Reimplemented from Xapian::Internal::PostList.

Definition at line 92 of file wrapperpostlist.cc.

References Xapian::Internal::PostList::count_matching_subqs(), and pl.

◆ get_description()

std::string WrapperPostList::get_description ( ) const

virtual

Return a string description of this object.

Implements Xapian::Internal::PostList.

Definition at line 80 of file wrapperpostlist.cc.

References Xapian::Internal::PostList::get_description(), and pl.

◆ get_docid()

Xapian::docid WrapperPostList::get_docid ( ) const

virtual

Return the current docid.

Implements Xapian::Internal::PostList.

Definition at line 26 of file wrapperpostlist.cc.

References Xapian::Internal::PostList::get_docid(), and pl.

◆ get_wdf()

Xapian::termcount WrapperPostList::get_wdf ( ) const

virtual

Return the wdf for the document at the current position.

The default implementation throws Xapian::UnimplementedError.

Reimplemented from Xapian::Internal::PostList.

Definition at line 86 of file wrapperpostlist.cc.

References Xapian::Internal::PostList::get_wdf(), and pl.

Referenced by SynonymPostList::get_weight().

◆ get_weight()

double WrapperPostList::get_weight	(	Xapian::termcount	doclen,
		Xapian::termcount	unique_terms,
		Xapian::termcount	wdfdocmax
	)		const

virtual

Return the weight contribution for the current position.

Implements Xapian::Internal::PostList.

Definition at line 32 of file wrapperpostlist.cc.

References Xapian::Internal::PostList::get_weight(), and pl.

◆ next()

PostList * WrapperPostList::next ( double w_min )

virtual

Advance the current position to the next document in the postlist.

The list starts before the first entry in the list, so next(), skip_to() or check() must be called before any methods which need the context of the current position.

Parameters

w_min The minimum weight contribution that is needed (this is just a hint which PostList subclasses may ignore).

Returns: If a non-NULL pointer is returned, then the caller should substitute the returned pointer for its pointer to us, and then delete us. This "pruning" can only happen for a non-leaf subclass of this class.

Implements Xapian::Internal::PostList.

Definition at line 58 of file wrapperpostlist.cc.

References Xapian::Internal::PostList::next(), and pl.

◆ operator=()

void WrapperPostList::operator= ( const WrapperPostList & )

privatedelete

Don't allow assignment.

◆ read_position_list()

PositionList * WrapperPostList::read_position_list ( )

virtual

Read the position list for the term in the current document and return a pointer to it (owned by the PostList).

The default implementation throws Xapian::UnimplementedError.

Reimplemented from Xapian::Internal::PostList.

Definition at line 52 of file wrapperpostlist.cc.

References pl, and Xapian::Internal::PostList::read_position_list().

◆ recalc_maxweight()

double WrapperPostList::recalc_maxweight ( )

virtual

Recalculate the upper bound on what get_weight() can return.

The maximum weight that get_weight() can return can decrease as the match progresses (typically when the PostList tree prunes) - calling this method calculates a current upper bound.

Note that this method may be called after the postlist has reached the end. In this situation, the method should return 0.

Implements Xapian::Internal::PostList.

Definition at line 46 of file wrapperpostlist.cc.

References pl, and Xapian::Internal::PostList::recalc_maxweight().

◆ skip_to()

PostList * WrapperPostList::skip_to	(	Xapian::docid	did,
		double	w_min
	)

virtual

Skip forward to the specified docid.

If the specified docid isn't in the list, position ourselves on the first document after it (or at_end() if no greater docids are present).

Parameters

w_min The minimum weight contribution that is needed (this is just a hint which PostList subclasses may ignore).

Returns: If a non-NULL pointer is returned, then the caller should substitute the returned pointer for its pointer to us, and then delete us. This "pruning" can only happen for a non-leaf subclass of this class.

Implements Xapian::Internal::PostList.

Definition at line 69 of file wrapperpostlist.cc.

References pl, and Xapian::Internal::PostList::skip_to().

Referenced by SynonymPostList::skip_to().