When you add the eval, it evaluates the regular expression as a string. This will likely remove one layer of backslashes ("escapes").

I wonder where you got the idea of wrapping eval around a regular expression definition from and why you think it would change the program outcome to one you expect?

In reply to Re: Repeated code blocks in long and hairy regex by Corion
in thread Repeated code blocks in long and hairy regex by Polyglot

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