Add a new Psl\Str\reverse() function

[yivi]

Psl\Str\Byte\reverse() exists, providing the functionality of strrev(), but there is no multibyte equivalent on the Psl\Str namespace.

This still breaks on some complex characters, as some multi byte emojis, but for that it would probably better to create a Psl\Str\Grapheme\reverse() for completion sake.

[coveralls]

Pull Request Test Coverage Report for Build 1354621226

• 2 of 2 (100.0%) changed or added relevant lines in 1 file are covered.
• No unchanged relevant lines lost coverage.
• Overall coverage increased (+4.0e**-05%**) to 99.936%

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Totals
Change from base Build 1328169160:	4.0e-05%
Covered Lines:	3125
Relevant Lines:	3127

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💛 - Coveralls

[yivi]

Mmmh. I think this would be better accomplished with a regex_split. With this it would be possible to capture multibyte extended unicode sequences:

use Psl\Vec;

$rev_array = Vec\reverse(\preg_split('/(\X)/u', $string, -1, \PREG_SPLIT_DELIM_CAPTURE | \PREG_SPLIT_NO_EMPTY));

I've been testing and this would work with much more complex unicode sequences.

The "problem" is that as far as I can see, we cannot pass additional flags to Regex\split()

For a use-case like this, would using the native preg_split() over the Psl version be fine?

Also, going through preg_split instead of mb_* functions would make $encoding not needed. Which I don't know if it's a good or a bad thing.

[azjezz]

I think that's not needed, I'm happy with the current version, and i don't think we need to overdo it here.

[yivi]

Good. Thanks for all your help.

Further checking shows that the regex version also seems to choke with extended unicode chars (trying with emojis like this '👩‍👩‍👦👩🏽‍❤️‍👨🏼👩🏽‍🏫', given my ignorance of more interesting languages).

Would it be ok if I also created a PR for Str\Grapheme\reverse(), for completeness sake?

[azjezz]

Would it be ok if I also created a PR for Str\Grapheme\reverse(), for completeness sake?

Yes, i think that would be a nice addition as well :)