strus::QueryExpression Class Reference

Object representing a sequence of query operations to get the set of postings (d,p) of an atomic term or an expression. More...

#include <bindingObjects.hpp>

Public Member Functions
	QueryExpression (const QueryExpression &o)
	QueryExpression ()
void	pushTerm (const String &type_, const String &value_, const Index &length_)
	Add operation "Push a single term on the stack". More...
void	pushDocField (const String &metadata_start_, const String &metadata_end_)
	Add operation "Push a single document field specification on the stack". More...
void	pushExpression (const String &opname_, unsigned int argc_, int range_=0, unsigned int cardinality_=0)
	Add operation "Create an expression from the topmost 'argc' elements of the stack, pop them from the stack and push the expression as single unit on the stack". More...
void	attachVariable (const String &name_)
	Add operation "Attach a variable to the top expression or term on the query stack". More...
void	add (const QueryExpression &o)
	Appends the operations of 'o' to this. More...
std::size_t	size () const
	Get the number of items (sub expressions) on the stack as result of this expression. More...

Friends
class	Query

Detailed Description

Object representing a sequence of query operations to get the set of postings (d,p) of an atomic term or an expression.

Constructor & Destructor Documentation

strus::QueryExpression::QueryExpression ( const QueryExpression &  o )

inline

strus::QueryExpression::QueryExpression ( )

inline

Member Function Documentation

void strus::QueryExpression::add

(

const QueryExpression &

o

)

Appends the operations of 'o' to this.

Parameters

[in]

o

expression to copy

void strus::QueryExpression::attachVariable

(

const String &

name_

)

Add operation "Attach a variable to the top expression or term on the query stack".

Note

The positions of the query matches of the referenced term or expression can be accessed through this variable in summarization.

Parameters

[in]

name_

name of the variable attached

Remarks

The stack is not changed

void strus::QueryExpression::pushDocField	(	const String &	metadata_start_,
		const String &	metadata_end_
	)

Add operation "Push a single document field specification on the stack".

Parameters

[in]	metadata_start_	name of meta data element that defines the start of the document field, assumed as 1 if name is empty
[in]	metadata_end_	name of meta data element that defines the end of the document field, assumed as max value if name is empty

void strus::QueryExpression::pushExpression	(	const String &	opname_,
		unsigned int	argc_,
		int	range_ = 0,
		unsigned int	cardinality_ = 0
	)

Add operation "Create an expression from the topmost 'argc' elements of the stack, pop them from the stack and push the expression as single unit on the stack".

Parameters

[in]	opname_	name of the expression operator
[in]	argc_	number of operands (topmost elements from stack) of the expression
[in]	range_	range number for the expression span in the document
[in]	cardinality_	number that specifies the minimum size of a subset or subset permutation to match

void strus::QueryExpression::pushTerm	(	const String &	type_,
		const String &	value_,
		const Index &	length_
	)

Add operation "Push a single term on the stack".

Parameters

[in]	type_	query term type name
[in]	value_	query term value
[in]	length_	length of the feature (ordinal position count)

std::size_t strus::QueryExpression::size ( ) const

inline

Get the number of items (sub expressions) on the stack as result of this expression.

Returns

the number of items (sub expressions)

Friends And Related Function Documentation

friend class Query

friend

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The documentation for this class was generated from the following file:

• /home/patrick/Projects/github/strusBindings/include/strus/bindingObjects.hpp