Text::Query::ParseAdvanced - Parse AltaVista advanced query syntax

NAME

Text::Query::ParseAdvanced - Parse AltaVista advanced query syntax

SYNOPSIS

  use Text::Query;
  my $q=new Text::Query('hello and world',
                        -parse => 'Text::Query::ParseAdvanced',
                        -solve => 'Text::Query::SolveAdvancedString',
                        -build => 'Text::Query::BuildAdvancedString');

DESCRIPTION

This module provides an object that parses a string containing a Boolean query expression similar to an AltaVista ``advanced query''.

It's base class is Text::Query::Parse;

Query expressions consist of literal strings (or regexps) joined by the following operators, in order of precedence from lowest to highest:

OR, |
AND, &
NEAR, ~
NOT, !

Operator names are not case-sensitive. Note that if you want to use a | in a regexp, you need to backwhack it to keep it from being seen as a query operator. Sub-expressions may be quoted in single or double quotes to match ``and,'' ``or,'' or ``not'' literally and may be grouped in parentheses ((, )) to alter the precedence of evaluation.

A parenthesized sub-expression may also be concatenated with other sub- expressions to match sequences: (Perl or Python) interpreter would match either ``Perl interpreter'' or ``Python interpreter''. Concatenation has a precedence higher than NOT but lower than AND. Juxtaposition of simple words has the highest precedence of all.

OPTIONS

These are the additional options of the prepare method and the constructor.

-near defaults to 10

Sets the number of words that can occur between two expressions and still satisfy the NEAR operator.

-operators defaults to and, or, not, near

Sets the operator names. The argument of the option is a pointer to a hash table mapping the default names to desired names. For instance:

    {
        'or' => 'ou',
        'and' => 'et',
        'near' => 'proche',
        'not' => 'non',
    }

-scope_map default to {}

Map the scope names to other names. If a scope is specified as scope: search the map for an entry whose key is scope and replace scope with the scalar found. For instance:

     {
         'scope' => 'otherscope'
     }

AUTHORS

Eric Bohlman (ebohlman@netcom.com)