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|
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 3.2//EN">
<html>
<head>
<title>SWISH-Enhanced: SWISH::API - Perl interface to the Swish-e C Library </title>
<link href="./style.css" rel=stylesheet type="text/css" title="refstyle">
</head>
<body>
<h1 class="banner">
<a href="http://swish-e.org"><img border=0 src="images/swish.gif" alt="Swish-E Logo"></a><br>
<img src="images/swishbanner1.gif"><br>
<img src="images/dotrule1.gif"><br>
SWISH::API - Perl interface to the Swish-e C Library
</h1>
<hr>
<p>
<div class="navbar">
<a href="./SWISH-LIBRARY.html">Prev</a> |
<a href="./index.html">Contents</a> |
<a href="./swish.html">Next</a>
</div>
<p>
<div class="toc">
<A NAME="toc"></A>
<P><B>Table of Contents:</B></P>
<UL>
<LI><A HREF="#SYNOPSIS">SYNOPSIS</A>
<LI><A HREF="#DESCRIPTION">DESCRIPTION</A>
<LI><A HREF="#DEPENDENCIES">DEPENDENCIES</A>
<LI><A HREF="#OVERVIEW">OVERVIEW</A>
<LI><A HREF="#METHODS">METHODS</A>
<UL>
<LI><A HREF="#SWISH_API_Swish_Handle_Object">SWISH::API - Swish Handle Object</A>
<UL>
<LI><A HREF="#Error_Handling">Error Handling</A>
<LI><A HREF="#Generating_Search_and_Result_Objects">Generating Search and Result Objects</A>
</UL>
<LI><A HREF="#SWISH_API_Search_Search_Objects">SWISH::API::Search - Search Objects</A>
<LI><A HREF="#SWISH_API_Results_Generating_and_accessing_results">SWISH::API::Results - Generating and accessing results</A>
<LI><A HREF="#Results_Methods">Results Methods</A>
<LI><A HREF="#SWISH_API_Result_Result_Methods">SWISH::API::Result - Result Methods</A>
<LI><A HREF="#Utility_Methods">Utility Methods</A>
</UL>
<LI><A HREF="#NOTES">NOTES</A>
<LI><A HREF="#COPYRIGHT">COPYRIGHT</A>
<LI><A HREF="#AUTHOR">AUTHOR</A>
<LI><A HREF="#SUPPORT">SUPPORT</A>
</UL>
</div>
[ <B><FONT SIZE=-1><A HREF="#toc">TOC</A></FONT></B> ]
<HR>
<P>
<H1><A NAME="SYNOPSIS">SYNOPSIS</A></H1>
<P>
<table>
<tr>
<td bgcolor="#eeeeee" width="1">
</td>
<td>
<pre> use SWISH::API;</pre>
</td>
</tr>
</table>
<P>
<table>
<tr>
<td bgcolor="#eeeeee" width="1">
</td>
<td>
<pre> my $swish = SWISH::API->new( 'index.swish-e' );</pre>
</td>
</tr>
</table>
<P>
<table>
<tr>
<td bgcolor="#eeeeee" width="1">
</td>
<td>
<pre> $swish->AbortLastError
if $swish->Error;</pre>
</td>
</tr>
</table>
<P>
<table>
<tr>
<td bgcolor="#eeeeee" width="1">
</td>
<td>
<pre> # A short-cut way to search</pre>
</td>
</tr>
</table>
<P>
<table>
<tr>
<td bgcolor="#eeeeee" width="1">
</td>
<td>
<pre> my $results = $swish->Query( "foo OR bar" );</pre>
</td>
</tr>
</table>
<P>
<table>
<tr>
<td bgcolor="#eeeeee" width="1">
</td>
<td>
<pre> # Or more typically
my $search = $swish->New_Search_Object;</pre>
</td>
</tr>
</table>
<P>
<table>
<tr>
<td bgcolor="#eeeeee" width="1">
</td>
<td>
<pre> # then in a loop
my $results = $search->Execute( $query );</pre>
</td>
</tr>
</table>
<P>
<table>
<tr>
<td bgcolor="#eeeeee" width="1">
</td>
<td>
<pre> # always check for errors (but aborting is not always necessary)</pre>
</td>
</tr>
</table>
<P>
<table>
<tr>
<td bgcolor="#eeeeee" width="1">
</td>
<td>
<pre> $swish->AbortLastError
if $swish->Error;</pre>
</td>
</tr>
</table>
<P>
<table>
<tr>
<td bgcolor="#eeeeee" width="1">
</td>
<td>
<pre> # Display a list of results</pre>
</td>
</tr>
</table>
<P>
<table>
<tr>
<td bgcolor="#eeeeee" width="1">
</td>
<td>
<pre> my $hits = $results->Hits;
if ( !$hits ) {
print "No Results\n";
return; /* for example *.
}</pre>
</td>
</tr>
</table>
<P>
<table>
<tr>
<td bgcolor="#eeeeee" width="1">
</td>
<td>
<pre> print "Found ", $results->Hits, " hits\n";</pre>
</td>
</tr>
</table>
<P>
<table>
<tr>
<td bgcolor="#eeeeee" width="1">
</td>
<td>
<pre> # Seek to a given page - should check for errors
$results->SeekResult( ($page-1) * $page_size );</pre>
</td>
</tr>
</table>
<P>
<table>
<tr>
<td bgcolor="#eeeeee" width="1">
</td>
<td>
<pre> while ( my $result = $results->NextResult ) {
printf("Path: %s\n Rank: %lu\n Size: %lu\n Title: %s\n Index: %s\n Modified: %s\n Record #: %lu\n File #: %lu\n\n",
$result->Property( "swishdocpath" ),
$result->Property( "swishrank" ),
$result->Property( "swishdocsize" ),
$result->Property( "swishtitle" ),
$result->Property( "swishdbfile" ),
$result->ResultPropertyStr( "swishlastmodified" ),
$result->Property( "swishreccount" ),
$result->Property( "swishfilenum" )
);
}</pre>
</td>
</tr>
</table>
<P>
<table>
<tr>
<td bgcolor="#eeeeee" width="1">
</td>
<td>
<pre> # display properties and metanames</pre>
</td>
</tr>
</table>
<P>
<table>
<tr>
<td bgcolor="#eeeeee" width="1">
</td>
<td>
<pre> for my $index_name ( $swish->IndexNames ) {
my @metas = $swish->MetaList( $index_name );
my @props = $swish->PropertyList( $index_name );</pre>
</td>
</tr>
</table>
<P>
<table>
<tr>
<td bgcolor="#eeeeee" width="1">
</td>
<td>
<pre> for my $m ( @metas ) {
my $name = $m->Name;
my $id = $m->ID;
my $type = $m->Type;
}
# (repeat above for @props)
}</pre>
</td>
</tr>
</table>
<P>
[ <B><FONT SIZE=-1><A HREF="#toc">TOC</A></FONT></B> ]
<HR>
<H1><A NAME="DESCRIPTION">DESCRIPTION</A></H1>
<P>
This module provides a Perl interface to the Swish-e search engine. This
module allows embedding the swish-e search code into your application
avoiding the need to fork to run the swish-e binary and to keep an index
file open when running multiple queries. This results in increased search
performance.
<P>
[ <B><FONT SIZE=-1><A HREF="#toc">TOC</A></FONT></B> ]
<HR>
<H1><A NAME="DEPENDENCIES">DEPENDENCIES</A></H1>
<P>
You must have installed Swish-e version 2.4 before building this module.
Download from:
<P>
<table>
<tr>
<td bgcolor="#eeeeee" width="1">
</td>
<td>
<pre> <A HREF="http://swish-e.org">http://swish-e.org</A></pre>
</td>
</tr>
</table>
<P>
[ <B><FONT SIZE=-1><A HREF="#toc">TOC</A></FONT></B> ]
<HR>
<H1><A NAME="OVERVIEW">OVERVIEW</A></H1>
<P>
This module includes a number of classes.
<P>
Searching consists of connecting to a swish-e index (or indexes), and then
running queries against the open index. Connecting to the index creates a
swish object blessed into the SWISH::API class.
<P>
A SWISH::API::Search object is created from the SWISH::API object. The
SWISH::API::Search object can have associated parameters (e.g. result sort
order).
<P>
The SWISH::API::Search object is used to query the associated index file or
files. A query on a search object returns a results object of the class
SWISH::API::Results. Then individual results of the SWISH::API::Result
class can be fetched by calling a method of the results object.
<P>
Finally, a result's properties can be accessed by calling methods on the
result object.
<P>
[ <B><FONT SIZE=-1><A HREF="#toc">TOC</A></FONT></B> ]
<HR>
<H1><A NAME="METHODS">METHODS</A></H1>
<P>
[ <B><FONT SIZE=-1><A HREF="#toc">TOC</A></FONT></B> ]
<HR>
<H2><A NAME="SWISH_API_Swish_Handle_Object">SWISH::API - Swish Handle Object</A></H2>
<P>
To begin using Swish you must first create a Swish Handle object. This
object makes the connection to one or more index files and is used to
create objects used for searching the associated index files.
<DL>
<P><DT><STRONG><A NAME="item__swish">$swish = SWISH::API->new( $index_files );</A></STRONG><DD>
<P>
This method returns a swish handle object blessed into the SWISH::API
class. <CODE>$index_files</CODE> is a space separated list of index files
to open. This always returns an object, even on errors. Caller must check
for errors (see below).
<P><DT><STRONG><A NAME="item__indexes">@indexes = $swish->IndexNames;</A></STRONG><DD>
<P>
Returns a list of index names associated with the swish handle. These were
the indexes specified as a parameter on the SWISH::API->new call. This
can be used in calls below that require specifying the index file name.
<P><DT><STRONG><A NAME="item__header_names">@header_names = $swish->HeaderNames;</A></STRONG><DD>
<P>
Returns a list of possible header names. These can be used to lookup header
values. See <CODE>SwishHeaderValue</CODE> method below.
<P><DT><STRONG><A NAME="item__values">@values = $swish->HeaderValue( $index_file, $header_name );</A></STRONG><DD>
<P>
A swish-e index has data associated with it stored in the index header.
This method provides access to that data.
<P>
Returns the header value for the header and index file specified. Most
headers are a single item, but some headers (e.g. "Stopwords")
return a list.
<P>
The list of possible header names can be obtained from the SwishHeaderNames
method.
<P><DT><STRONG><A NAME="item__swish_RankScheme_">$swish->RankScheme( 0|1 );</A></STRONG><DD>
<P>
Similar to the -R option with the swish-e command line tool. The default
ranking scheme is 0. Set it to 1 to experiment with other ranking features.
See the SWISH-CONFIG documentation for more on ranking schemes.
</DL>
<P>
[ <B><FONT SIZE=-1><A HREF="#toc">TOC</A></FONT></B> ]
<HR>
<H3><A NAME="Error_Handling">Error Handling</A></H3>
<P>
All errors are stored in and accessed via the SWISH::API object (the Swish
Handle). That is, even an error that occurs when calling a method on a
result (SWISH::API::Result) object will store the error in the parent
SWISH:API object.
<P>
Check for errors after every method call. Some errors are critical errors
and will require destruction of the SWISH::API object. Critical errors will
typically only happen when attaching to the database and are errors such as
an invalid index file name, permissions errors, or passing invalid objects
to calls.
<P>
Typically, if you receive an error when attaching to an index file or files
you should assume that the error is critical and let the swish object fall
out of scope (and destroyed). Otherwise, if an error is detected you should
check if it is a critical error. If the error is not critical you may
continue using the objects that have been created (for example, an invalid
meta name will generate a non-critical error, so you may continue searching
using the same search object).
<P>
Error state is cleared upon a new query.
<P>
Again, all error methods need to be called on the parent swish object
<DL>
<P><DT><STRONG><A NAME="item__swish_Error">$swish->Error</A></STRONG><DD>
<P>
Returns true if an error occurred on the last operation. On errors the
value returned is the internal Swish-e error number (which is less than
zero).
<P><DT><STRONG><A NAME="item__swish_CriticalError">$swish->CriticalError</A></STRONG><DD>
<P>
Returns true if the last error was a critical error
<P><DT><STRONG><A NAME="item__swish_AbortLastError">$swish->AbortLastError</A></STRONG><DD>
<P>
Aborts the running program and prints an error message to STDERR.
<P><DT><STRONG><A NAME="item__str">$str = $swish->ErrorString</A></STRONG><DD>
<P>
Returns the string description of the current error (based on the value
returned by $swish->Error). This is a generic error string.
<P><DT><STRONG><A NAME="item__msg">$msg = $swish->LastErrorMsg</A></STRONG><DD>
<P>
Returns a string with specific information about the last error, if any.
For example, if a query of:
<P>
<table>
<tr>
<td bgcolor="#eeeeee" width="1">
</td>
<td>
<pre> badmeta=foo</pre>
</td>
</tr>
</table>
<P>
and "badmeta" is an invalid metaname $swish->ErrorString might
return "Unknown metaname", but $swish->LastErrorMsg might
return "badmeta".
</DL>
<P>
[ <B><FONT SIZE=-1><A HREF="#toc">TOC</A></FONT></B> ]
<HR>
<H3><A NAME="Generating_Search_and_Result_Objects">Generating Search and Result Objects</A></H3>
<DL>
<P><DT><STRONG><A NAME="item__search">$search = $swish->New_Search_Object( $query );</A></STRONG><DD>
<P>
This creates a new search object blessed into the SWISH::API::Search class.
The optional <CODE>$query</CODE> parameter is a query string to store in
the search object.
<P>
See the section on <CODE>SWISH::API::Search</CODE> for methods available on the returned object.
<P>
The advantage of this method is that a search object can be used for
multiple queries:
<P>
<table>
<tr>
<td bgcolor="#eeeeee" width="1">
</td>
<td>
<pre> $search = $swish->New_Search_Objet;
while ( $query = next_query() ) {
$results = $search->Execute( $query );
...
}</pre>
</td>
</tr>
</table>
<P><DT><STRONG><A NAME="item__results">$results = $swish->Query( $query );</A></STRONG><DD>
<P>
This is a short-cut which avoids the step of creating a separate search
object. It returns a results object blessed into the SWISH::API::Results
class described below.
<P>
This method basically is the equivalent of
<P>
<table>
<tr>
<td bgcolor="#eeeeee" width="1">
</td>
<td>
<pre> $results = $swish->New_Search_Object->Execute( $query );</pre>
</td>
</tr>
</table>
</DL>
<P>
[ <B><FONT SIZE=-1><A HREF="#toc">TOC</A></FONT></B> ]
<HR>
<H2><A NAME="SWISH_API_Search_Search_Objects">SWISH::API::Search - Search Objects</A></H2>
<P>
A search object holds the parameters used to generate a list of results.
These methods are used to adjust these parameters and to create the list of
results for the current set of search parameters.
<DL>
<P><DT><STRONG><A NAME="item__search_SetQuery_">$search->SetQuery( $query );</A></STRONG><DD>
<P>
This will set (or replace) the query string associated with a search
object. This method is typically not used as the query can be set when
executing the actual query or when creating a search object.
<P><DT><STRONG><A NAME="item__search_SetStructure_">$search->SetStructure( $structure_bits );</A></STRONG><DD>
<P>
This method may change in the future.
<P>
A "structure" is a bit-mapped flag used to limit search results
to specific parts of an HTML document, such as the title or in H tags. The
possible bits are:
<P>
<table>
<tr>
<td bgcolor="#eeeeee" width="1">
</td>
<td>
<pre> IN_FILE = 1 This is the default
IN_TITLE = 2 In <title> tag
IN_HEAD = 4 In <head> tag
IN_BODY = 8 In <body>
IN_COMMENTS = 16 In html comments
IN_HEADER = 32 In <h*>
IN_EMPHASIZED = 64 In <em>, <b>, <strong>, <i>
IN_META = 128 In a meta tag (e.g. not swishdefault)</pre>
</td>
</tr>
</table>
<P>
So if you wish to limit your searches to words in heading tags (e.g. <H1>) or in the <title> tag use:
<P>
<table>
<tr>
<td bgcolor="#eeeeee" width="1">
</td>
<td>
<pre> $search->SetStructure( IN_HEAD | IN_TITLE );</pre>
</td>
</tr>
</table>
<P><DT><STRONG><A NAME="item__search_PhraseDelimiter_">$search->PhraseDelimiter( $char );</A></STRONG><DD>
<P>
Sets the character used as the phrase delimiter in searches. The default is
double-quotes (").
<P><DT><STRONG><A NAME="item__search_SetSearchLimit_">$search->SetSearchLimit( $property, $low, $high );</A></STRONG><DD>
<P>
Sets a range from <CODE>$low</CODE> to <CODE>$high</CODE> inclusive that
the give <CODE>$property</CODE> must be in to be selected as a result. Call
multiple times to set more than one limit on different properties. Limits
are ANDed, that is, a result must be within the range of all limits
specified to be included in a list of results.
<P>
For example to limit searches to documents modified in the last 48 hours:
<P>
<table>
<tr>
<td bgcolor="#eeeeee" width="1">
</td>
<td>
<pre> my $start = time - 48 * 60 * 60;
$search->SetSearchLimit( 'swishlastmodified', $start, time() );</pre>
</td>
</tr>
</table>
<P>
An error will be set if the property has already been specified or if
<CODE>$high</CODE> < $low.
<P>
Other errors may not be reported until running the query, such as the
property name is invalid or if <CODE>$low</CODE> or <CODE>$high</CODE> are
not numeric and the property specified is a numeric property.
<P>
Once a query is run you cannot change the limit settings without calling
the ResetSearchLimit method first.
<P><DT><STRONG><A NAME="item__search_ResetSearchLimit_">$search->ResetSearchLimit;</A></STRONG><DD>
<P>
Clears the limit parameters for the given object. This must be called if
the limit parameters need to be changed.
<P><DT><STRONG><A NAME="item__search_SetSort_">$search->SetSort( $sort_string );</A></STRONG><DD>
<P>
Sets the sort order of search results. The string is a space separated list
of valid document properties. Each property may contain a qualifier that
sets the direction of the sort.
<P>
For example, to sort the results by path name in ascending order and by
rank in descending order:
<P>
<table>
<tr>
<td bgcolor="#eeeeee" width="1">
</td>
<td>
<pre> $search->SetSort( 'swishdocpath asc swishrank desc' );</pre>
</td>
</tr>
</table>
<P>
The "asc" and "desc" qualifiers are optional, and if
omitted ascending is assumed.
<P>
Currently, errors (e.g invalid property name) are not detected on this
call, but rather when executing a query. This may change in the future.
</DL>
<P>
[ <B><FONT SIZE=-1><A HREF="#toc">TOC</A></FONT></B> ]
<HR>
<H2><A NAME="SWISH_API_Results_Generating_and_accessing_results">SWISH::API::Results - Generating and accessing results</A></H2>
<P>
Searching generates a results object blessed into the SWISH::API::Results
class.
<DL>
<P><DT><STRONG>$results = $search->Execute( $query );</STRONG><DD>
<P>
Executes a query based on the parameters in the search object.
<CODE>$query</CODE> is an optional query string to use for the search
($query replaces the set query string in the search object).
<P>
A typical use would be to create a search object once and then call this
method for each query using the same search object changing only the passed
in $query.
<P>
The caller should check for errors after making this all.
</DL>
<P>
[ <B><FONT SIZE=-1><A HREF="#toc">TOC</A></FONT></B> ]
<HR>
<H2><A NAME="Results_Methods">Results Methods</A></H2>
<P>
A query creates a results object that contains information about the query
(e.g. number of hits) and access to the individual results.
<DL>
<P><DT><STRONG><A NAME="item__hits">$hits = $results->Hits;</A></STRONG><DD>
<P>
Returns the number of results for the query. If zero and no errors were
reported after calling $search->Execute then the query returned zero
results.
<P><DT><STRONG><A NAME="item__parsed_words">@parsed_words = $results->ParsedWords( $index_name );</A></STRONG><DD>
<P>
Returns an array of tokenized words and operators with stopwords removed.
This is the array of tokens used by swish for the query.
<P>
<CODE>$index_name</CODE> must match one of the index files specified on the
creation of the swish object (via the SWISH::API->new call).
<P>
The parsed words are useful for highlighting search terms in associated
documents.
<P><DT><STRONG><A NAME="item__removed_stopwords">@removed_stopwords = $results->RemovedStopwords( $index_name) ;</A></STRONG><DD>
<P>
Returns an array of stopwords removed from a query, if any, for the index
specified.
<P>
<CODE>$index_name</CODE> must match one of the index files specified on the
creation of the swish object (via the SWISH::API->new call).
<P><DT><STRONG><A NAME="item__results_SeekResult_">$results->SeekResult( $position );</A></STRONG><DD>
<P>
Seeks to the position specified in the result list. Zero is the first
position and $results->Hits-1 is the last position. Seeking past the end
of results sets a non-critical error condition.
<P>
Useful for seeking to a specific "page" of results.
<P><DT><STRONG><A NAME="item__result">$result = $results->NextResult;</A></STRONG><DD>
<P>
Fetches the next result from the list of results. Returns undef if no more
results are available. <CODE>$result</CODE> is an object blessed into the
SWISH::API::Result class.
</DL>
<P>
[ <B><FONT SIZE=-1><A HREF="#toc">TOC</A></FONT></B> ]
<HR>
<H2><A NAME="SWISH_API_Result_Result_Methods">SWISH::API::Result - Result Methods</A></H2>
<P>
The follow methods provide access to data related to an individual result.
<DL>
<P><DT><STRONG><A NAME="item__prop">$prop = $result->Property( $prop_name );</A></STRONG><DD>
<P>
Fetches the property specified for the current result. An invalid property
name will cause an exception (which can be caught by wrapping the call in
an eval block).
<P>
Can return undefined.
<P>
Date properties are returned as a timestamp. Use something like
Date::Format to format the strings (or just call scalar
<CODE>localtime(</CODE> <CODE>$prop</CODE> ) ).
<P><DT><STRONG>$prop = $result->ResultPropertyStr( $prop_name );</STRONG><DD>
<P>
Fetches and formats the property. Unlike above, invalid property names
return the string "(null)" -- this will likely change to match
the above (i.e. throw an exception).
<P>
Undefined values are returned at the null string ("").
<P><DT><STRONG><A NAME="item__value">$value = $result->ResultIndexValue( $header_name );</A></STRONG><DD>
<P>
Returns the header value specified. This is similar to
$swish->HeaderValue(), but the index file is not specified (it is
determined by the result).
</DL>
<P>
[ <B><FONT SIZE=-1><A HREF="#toc">TOC</A></FONT></B> ]
<HR>
<H2><A NAME="Utility_Methods">Utility Methods</A></H2>
<DL>
<P><DT><STRONG><A NAME="item__metas">@metas = $swish->MetaList( $index_name );</A></STRONG><DD>
<P>
Swish-e has "MetaNames" which allow searching by fields in the
index. This method returns information about the Metanames.
<P>
Pass in the name of an open index file name and returns a list of
SWISH::API::MetaName objects. Three methods are currently defined on these
objects:
<P>
<table>
<tr>
<td bgcolor="#eeeeee" width="1">
</td>
<td>
<pre> $meta->Name;
$meta->ID;
$meta->Type;</pre>
</td>
</tr>
</table>
<P>
Name returns the name of the meta as defined in the MetaNames config option
when the index was created.
<P>
The ID is the internal ID number used to represent the meta name.
<P>
Type is the type of metaname. Currently only one type exists and its value
is zero.
<P><DT><STRONG><A NAME="item__props">@props = $swish->PropertyList( $index_name );</A></STRONG><DD>
<P>
Swish-e can store content or "properties" in the index and return
this data when running a query. A document's path, URL, title, size, date
or summary are examples of properites. Each property is accessed via its
PropertyName. This method returns information about the PropertNames stored
in the index.
<P>
Pass in the name of an open index file name and returns a list of
SWISH::API::MetaName objects. Three methods are currently defined on these
objects:
<P>
<table>
<tr>
<td bgcolor="#eeeeee" width="1">
</td>
<td>
<pre> $prop->Name;
$prop->ID;
$prop->Type;</pre>
</td>
</tr>
</table>
<P>
Name returns the name of the meta as defined in the MetaNames config option
when the index was created.
<P>
The ID is the internal ID number used to represent the meta name.
<P>
Type is the type of metaname. Currently only one type exists and its value
is zero.
<P><DT><STRONG><A NAME="item__propes">@propes = $result->PropertyList;</A></STRONG><DD>
<P><DT><STRONG><A NAME="item__meta">@meta = $result->MetaList;</A></STRONG><DD>
<P>
These also return a list of Property or Metaname description objects, but
are accessed via a result record. Since the result comes from a specific
index file there's no need to specify the index file name.
<P><DT><STRONG><A NAME="item__stemmed_word">$stemmed_word = $swish->StemWord( $word );</A></STRONG><DD>
<P>
*Deprecated*
<P>
Returns the stemmed version of the passed in word.
<P>
Deprecated because only stems using the original Porter Stemmer and uses a
shared memory location in the SW_HANDLE object to store the stemmed word.
See below for other stemming options.
<P><DT><STRONG><A NAME="item__fuzzy_word">$fuzzy_word = $swish->Fuzzy( $indexname, $word );</A></STRONG><DD>
<P>
Like StemWord used to work, only it uses whatever stemmer is named in
$indexname. Returns the same kind of fuzzy_word object as the
<CODE>FuzzyWord()</CODE> method.
<P><DT><STRONG><A NAME="item__mode_string">$mode_string = $result->FuzzyMode;</A></STRONG><DD>
<P>
Returns the string (e.g. "Stemming_en", "Soundex",
"None" ) indicating the stemming method used while indexing the
given document.
<P><DT><STRONG>$fuzzy_word = $result->FuzzyWord( $word );</STRONG><DD>
<P>
Converts <CODE>$word</CODE> using the same fuzzy mode used to index the
$result. Returns a SWISH::API::FuzzyWord object. Methods on the object are
used to access the converted words and other data as shown below.
<P><DT><STRONG><A NAME="item__count">$count = $fuzzy_word->WordCount;</A></STRONG><DD>
<P>
Returns the number of output words. Normally this is the value one, but may
be more depending on the stemmer used. DoubleMetaphone can return two
strings for a single input string.
<P><DT><STRONG><A NAME="item__status">$status = $fuzzy_word->WordError;</A></STRONG><DD>
<P>
Returns any error code that the stemmer might set. Normally, this return
value is zero, indicating that the stemming/fuzzy operation succedded. The
values returned are defined in the swish-e source file /src/stemmer.h.
<P><DT><STRONG><A NAME="item__words">@words = $fuzzy_word->WordList;</A></STRONG><DD>
<P>
Returns the converted words from the stemming/fuzzy operation. Normally,
the array will contain a single element, although may contain more (i.e. if
DoubleMetaphone is used and the input word returns two strings).
<P>
In the event that a word does not stem (e.g. trying to stem a number), this
method will return the original input word specified when
$result->FuzzyWord( <CODE>$word</CODE> ) was called.
<P><DT><STRONG>@parsed_words = $swish->SwishWords( $string, $index_file );</STRONG><DD>
<P>
* Not implemented *
<P>
Splits up the input string into tokens of swish words and operators.
<H1><A NAME="NOTES">NOTES</A></H1>
<P>
Perl's garbage collection makes it easy to write code for searching with
Swish-e, but care must be taken not to keep objects around too long which
can use up memory.
<P>
Here's an example of a potential problem. Say you have a very large number
of documents indexed and you want to find the first hit for a number of
popular keywords (error checking omitted in this bad example):
<P>
<table>
<tr>
<td bgcolor="#eeeeee" width="1">
</td>
<td>
<pre> sub first_hit {
my $query = shift;
my $handle = SWISH::API->new( 'index.swish-e');
my $results = $handle->Query( $query );
my $first_hit = $results->NextResult;
return $first_hit;
}</pre>
</td>
</tr>
</table>
<P>
<table>
<tr>
<td bgcolor="#eeeeee" width="1">
</td>
<td>
<pre> my @first_hit_list;
for ( @keywords )
push @first_hit_list, $first_hit($_);
}</pre>
</td>
</tr>
</table>
<P>
The <CODE>first_hit()</CODE> subroutine is returning a SWISH::Result
object. That makes it easy to access properties:
<P>
<table>
<tr>
<td bgcolor="#eeeeee" width="1">
</td>
<td>
<pre> # print file names
for my $result ( @first_hit_list ) {
print $result->Property('swishdocpath'),"\n";
}</pre>
</td>
</tr>
</table>
<P>
But as long as a SWISH::API::Result object is around, so is the entire list
of results generated by the $handle->Query() call, and the index file is
still open (because a SWISH::API::Result depends on a SWISH::API::Results
object, which depends on a SWISH::API object).
<P>
In this case it would be better to return from <CODE>first_hit()</CODE>
just the properties you need:
<P>
<table>
<tr>
<td bgcolor="#eeeeee" width="1">
</td>
<td>
<pre> ...
my $first_hit = $results->NextResult;
return $first_hit->Property('swishdocpath');
}</pre>
</td>
</tr>
</table>
<P>
Then when <CODE>first_hit()</CODE> sub ends the result list will be freed,
and the index file closed, thanks to Perl's reference count tracking.
<P>
Note: the other problem with the above code is that the same index file is
opened for each call to the function. Don't do that, instead open the index
file once.
<H1><A NAME="COPYRIGHT">COPYRIGHT</A></H1>
<P>
This library is free software; you can redistribute it and/or modify it
under the same terms as Perl itself.
<H1><A NAME="AUTHOR">AUTHOR</A></H1>
<P>
Bill Moseley <A HREF="mailto:moseley@hank.org.">moseley@hank.org.</A>
2002/2003/2004
<H1><A NAME="SUPPORT">SUPPORT</A></H1>
<P>
Please contact the Swish-e discussion email list for support with this
module or with Swish-e. Please do not contact the developers directly.
</DL>
[ <B><FONT SIZE=-1><A HREF="#toc">TOC</A></FONT></B> ]
<HR>
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<BR>SWISH-E is distributed with <B>no warranty</B> under the terms of the
<A HREF="http://www.fsf.org/copyleft/gpl.html">GNU Public License</A>,<BR>
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