One may do this with a logarithmic number of concatenations, though (instead of linear). I don't see a feasible way to do such a thing with StringBuilder,

That may make concatenation faster than StringBuilder even in the case of a large number of strings.

I wonder how Perl's join actually works.

In reply to Re^2: Five Ways to Reverse a String of Words (C#, Perl 5, Perl6, Ruby, Haskell) by akho
in thread Five Ways to Reverse a String of Words (C#, Perl 5, Perl 6, Ruby, Haskell) by eyepopslikeamosquito

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