[ruby-core:115815] [Ruby master Feature#20049] Destructive drop_while for Array and Hash

Issue #20049 has been updated by zverok (Victor Shepelev).


> Could you explain the use-case for the new method, please?

Not the original author, but I think one of the frequent use cases is some parser- or scanner-alike code. E.g., after reading some "dirty" data, 

```ruby
lines.drop_while! { ln.match?(/HEADER:/) }

# operate with clean `lines` here
```

(I had more generic take on this in my ticket about "consuming" enumerators #19061, which I haven't had time to pursue the better proposal/explanation this year, but want to return during the next one.)

----------------------------------------
Feature #20049: Destructive drop_while for Array and Hash
https://bugs.ruby-lang.org/issues/20049#change-105764

* Author: chucke (Tiago Cardoso)
* Status: Feedback
* Priority: Normal
----------------------------------------
I propose a "drop_while!" variant for arrays and hashes, which changes the current instance.

```ruby
h = {foo: 0, bar: 1, baz: 2}
h.drop_while!{|element| key, value = *element; value < 2 }
h #=> # => { baz: 2 }
```



-- 
https://bugs.ruby-lang.org/
 ______________________________________________
 ruby-core mailing list -- [e-mail]
 To unsubscribe send an email to [e-mail]
 ruby-core info -- https://ml.ruby-lang.org/mailman3/postorius/lists/ruby-core.ml.ruby-lang.org/