man Text::Query::Build () - Base class for query builders
NAME
Text::Query::Build - Base class for query builders
SYNOPSIS
package Text::Query::BuildMy;
use Text::Query::Build;
use vars qw(@ISA);
@ISA = qw(Text::Query::Build);
DESCRIPTION
This module provides a virtual base class for query builders.
Query builders are called by the parser logic. A given set of functions is provided by the builder to match a Boolean logic. All the methods return a scalar corresponding to the code that performs the specified options.
Parameters Q1 and Q2 are the same type of scalar as the return values.
METHODS
- matchstring()
- Return a string that represent the last built expression. Two identical expressions should generate the same string. This is for testing purpose.
CODE-GENERATION METHODS
- build_init()
- Called before building the expression. A chance to initialize object data.
- build_final_expression(Q1)
- Does any final processing to generate code to match a top-level expression. The return value is NOT necessarily of a type that can be passed to the other code-generation methods.
- build_expression(Q1,Q2)
- Generate code to match CWQ1 OR CWQ2
- build_expression_finish(Q1)
- Generate any code needed to enclose an expression.
- build_conj(Q1,Q2,F)
- Generate code needed to match CWQ1 AND CWQ2. F will be true if this is the first time this method is called in a sequence of several conjunctions.
- build_near(Q1,Q2)
- Generate code needed to match CWQ1 NEAR CWQ2.
- build_concat(Q1,Q2)
- Generate code needed to match CWQ1 immediately followed by CWQ2.
- build_negation(Q1)
- Generate code needed to match NOT CWQ1.
- build_literal(Q1)
- Generate code to match CWQ1 as a literal.
- build_scope_start($scope)
- Generate code to enter in the CW$scope query context.
- build_scope_end($scope,Q1)
- Generate code needed to match CWQ1 in the CW$scope context.
- build_mandatory(Q1)
- Generate code to match CWQ1 (think + in AltaVista syntax).
- build_forbiden(Q1)
- Generate code to match NOT CWQ1 (think - in AltaVista syntax).
SEE ALSO
AUTHORS
Eric Bohlman (ebohlman@netcom.com)
Loic Dachary (loic@senga.org)