Anyhow, wouldn't it be nice if there was a way do easily choose between different engines?Yeah, but since there isn't an alternative engine available, and I've never seen anyone attempting to write an alternative regexp engine for Perl, it doesn't make sense to put effort into making switching regexp engines easy.
Write an alternative engine, and I'll bet someone will make a pragma to switch between them. That happened with 'sort' as well. After making merge sort available for Perl, the sort pragma was created.
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