s/(\d+(?:\.\d*)?|\d*\.\d+)/sprintf("%.2f", $1)/eg;    #  :)

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I really can't think of a way to do this in a pure regex. You've got some logic in there (like the addition of zeros where there aren't enough) that I can't think of a way to express in a regular expression while accomplishing the rest of your requirements, short of using program logic like above. Even if there is a solution, I suspect it will make use of Perl's advanced regular expression features and would thus be unportable to JavaScript.

I'm interested in seeing if there are any good responses, though.

In reply to Re: Re: Re: Using Regular Expressions to Simulate sprintf() function - One Liner Challenge by Fastolfe
in thread Using Regular Expressions to Simulate sprintf() function - One Liner Challenge by Incognito

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