Issue #17030 has been updated by marcandre (Marc-Andre Lafortune).


Couldn't static analysis of the code determine in most cases if match data need be generated or not?

This is Ruby, so I can think of some corner cases where things like `const_get(:Regexp).last_match` would be impacted (in theory), what other limitations would this have?

Maybe it would be best to start a different thread as none of these proposals have a relation to `grep{_v}` without block not being optimized.


----------------------------------------
Bug #17030: Enumerable#grep{_v} should be optimized for Regexp
https://bugs.ruby-lang.org/issues/17030#change-87196

* Author: marcandre (Marc-Andre Lafortune)
* Status: Open
* Priority: Normal
* Backport: 2.5: UNKNOWN, 2.6: UNKNOWN, 2.7: UNKNOWN
----------------------------------------
Currently:

```ruby
array.select { |e| e.match?(REGEXP) }

# about 3x faster and 6x more memory efficient than
array.grep(REGEXP)
```

This is because `grep` calls `Regexp#===` which creates useless `MatchData`



-- 
https://bugs.ruby-lang.org/

Unsubscribe: <mailto:ruby-core-request / ruby-lang.org?subject=unsubscribe>
<http://lists.ruby-lang.org/cgi-bin/mailman/options/ruby-core>