NAME¶
KinoSearch1::Analysis::Token - unit of text
SYNOPSIS¶
# private class - no public API
PRIVATE CLASS¶
You can't actually instantiate a Token object at the Perl level -- however, you
can affect individual Tokens within a TokenBatch by way of TokenBatch's
(experimental) API.
DESCRIPTION¶
Token is the fundamental unit used by KinoSearch1's Analyzer subclasses. Each
Token has 4 attributes: text, start_offset, end_offset, and pos_inc (for
position increment).
The text of a token is a string.
A Token's start_offset and end_offset locate it within a larger text, even if
the Token's text attribute gets modified -- by stemming, for instance. The
Token for "beating" in the text "beating a dead horse"
begins life with a start_offset of 0 and an end_offset of 7; after stemming,
the text is "beat", but the end_offset is still 7.
The position increment, which defaults to 1, is a an advanced tool for
manipulating phrase matching. Ordinarily, Tokens are assigned consecutive
position numbers: 0, 1, and 2 for "three blind mice". However, if
you set the position increment for "blind" to, say, 1000, then the
three tokens will end up assigned to positions 0, 1, and 1001 -- and will no
longer produce a phrase match for the query '"three blind mice"'.
COPYRIGHT¶
Copyright 2006-2010 Marvin Humphrey
LICENSE, DISCLAIMER, BUGS, etc.¶
See KinoSearch1 version 1.01.