[
https://issues.apache.org/jira/browse/LUCENE-2167?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=12838073#action_12838073
]
Robert Muir commented on LUCENE-2167:
-------------------------------------
btw, here is some statement that seems to confirm my suspicions, from the
standard:
In section 6.3, there is an example of the grapheme cluster boundaries
converted into a simple regex (the kind we could do easily in jflex now that it
has the properties available).
They make this statement: Such a regular expression can also be turned into a
fast, deterministic finite-state machine. Similar regular expressions are
possible for Word boundaries. Line and Sentence boundaries are more
complicated, and more difficult to represent with regular expressions.
> StandardTokenizer Javadoc does not correctly describe tokenization around
> punctuation characters
> ------------------------------------------------------------------------------------------------
>
> Key: LUCENE-2167
> URL: https://issues.apache.org/jira/browse/LUCENE-2167
> Project: Lucene - Java
> Issue Type: Bug
> Affects Versions: 2.4.1, 2.9, 2.9.1, 3.0
> Reporter: Shyamal Prasad
> Priority: Minor
> Attachments: LUCENE-2167.patch, LUCENE-2167.patch
>
> Original Estimate: 0.5h
> Remaining Estimate: 0.5h
>
> The Javadoc for StandardTokenizer states:
> {quote}
> Splits words at punctuation characters, removing punctuation.
> However, a dot that's not followed by whitespace is considered part of a
> token.
> Splits words at hyphens, unless there's a number in the token, in which case
> the whole
> token is interpreted as a product number and is not split.
> {quote}
> This is not accurate. The actual JFlex implementation treats hyphens
> interchangeably with
> punctuation. So, for example "video,mp4,test" results in a *single* token and
> not three tokens
> as the documentation would suggest.
> Additionally, the documentation suggests that "video-mp4-test-again" would
> become a single
> token, but in reality it results in two tokens: "video-mp4-test" and "again".
> IMHO the parser implementation is fine as is since it is hard to keep
> everyone happy, but it is probably
> worth cleaning up the documentation string.
> The patch included here updates the documentation string and adds a few test
> cases to confirm the cases described above.
--
This message is automatically generated by JIRA.
-
You can reply to this email to add a comment to the issue online.
---------------------------------------------------------------------
To unsubscribe, e-mail: java-dev-unsubscr...@lucene.apache.org
For additional commands, e-mail: java-dev-h...@lucene.apache.org
