[GitHub] [arrow-rs] tustvold opened a new pull request, #3812: Add regexp_match docs

["tustvold (via GitHub)" <gi...@apache.org>]

tustvold opened a new pull request, #3812:
URL: https://github.com/apache/arrow-rs/pull/3812

   # Which issue does this PR close?
   
   <!--
   We generally require a GitHub issue to be filed for all bug fixes and enhancements and this helps us generate change logs for our releases. You can link an issue to this PR using the GitHub syntax. For example `Closes #123` indicates that this PR will close issue #123.
   -->
   
   Closes #.
   
   # Rationale for this change
    
   <!--
   Why are you proposing this change? If this is already explained clearly in the issue then this section is not needed.
   Explaining clearly why changes are proposed helps reviewers understand your changes and offer better suggestions for fixes.
   -->
   
   Follow on to https://github.com/apache/arrow-rs/pull/3807 adds some docs of what the expected behaviour is
   
   # What changes are included in this PR?
   
   <!--
   There is no need to duplicate the description in the issue here but it is sometimes worth providing a summary of the individual changes in this PR.
   -->
   
   # Are there any user-facing changes?
   
   
   <!--
   If there are user-facing changes then we may require documentation to be updated before approving the PR.
   -->
   
   <!---
   If there are any breaking changes to public APIs, please add the `breaking change` label.
   -->
   


-- 
This is an automated message from the Apache Git Service.
To respond to the message, please log on to GitHub and use the
URL above to go to the specific comment.

To unsubscribe, e-mail: github-unsubscribe@arrow.apache.org

For queries about this service, please contact Infrastructure at:
users@infra.apache.org

[GitHub] [arrow-rs] viirya commented on a diff in pull request #3812: Add regexp_match docs

["viirya (via GitHub)" <gi...@apache.org>]

viirya commented on code in PR #3812:
URL: https://github.com/apache/arrow-rs/pull/3812#discussion_r1128158864


##########
arrow-string/src/regexp.rs:
##########
@@ -157,6 +157,26 @@ pub fn regexp_is_match_utf8_scalar<OffsetSize: OffsetSizeTrait>(
 }
 
 /// Extract all groups matched by a regular expression for a given String array.
+///
+/// Modelled after the Postgres [regexp_match].
+///
+/// Returns a ListArray of [`GenericStringArray`] with each element containing the leftmost-first
+/// match of the corresponding index in `regex_array` to string in `array`
+///
+/// If there is no match, the list element is NULL.
+///
+/// If a match is found, and the pattern contains no capturing parenthesized subexpressions,
+/// then the list element is a single-element [`GenericStringArray`] containing the substring
+/// matching the whole pattern.
+///
+/// If a match is found, and the pattern contains capturing parenthesized subexpressions, then the
+/// list element is a [`GenericStringArray`] whose n'th element is the substring matching
+/// the n'th capturing parenthesized subexpression of the pattern.
+///
+/// The flags parameter is an optional text string containing zero or more single-letter flags
+/// that change the function's behavior.
+///
+/// [regexp_matches]: https://www.postgresql.org/docs/current/functions-matching.html#FUNCTIONS-POSIX-REGEXP

Review Comment:
   I think you meant `regexp_match`?
   
   ```suggestion
   /// [regexp_match]: https://www.postgresql.org/docs/current/functions-matching.html#FUNCTIONS-POSIX-REGEXP
   ```



-- 
This is an automated message from the Apache Git Service.
To respond to the message, please log on to GitHub and use the
URL above to go to the specific comment.

To unsubscribe, e-mail: github-unsubscribe@arrow.apache.org

For queries about this service, please contact Infrastructure at:
users@infra.apache.org

[GitHub] [arrow-rs] tustvold merged pull request #3812: Add regexp_match docs

["tustvold (via GitHub)" <gi...@apache.org>]

tustvold merged PR #3812:
URL: https://github.com/apache/arrow-rs/pull/3812


-- 
This is an automated message from the Apache Git Service.
To respond to the message, please log on to GitHub and use the
URL above to go to the specific comment.

To unsubscribe, e-mail: github-unsubscribe@arrow.apache.org

For queries about this service, please contact Infrastructure at:
users@infra.apache.org