Hi monks,

I have a very complex regex that I want to do the back-referencing for the replacement...

$s =~ s/\ ((0?[1-9]|1[0-2])\/(0?[1-9]|[1-2][0-9]|3[0-1])\/(19|20)?[0-9
+][0-9](\s(((0?[0-9]|1[0-9]|2[0-3]):[0-5][0-9](:[0-5][0-9])?)|((0?[0-9
+]|1[0-2]):[0-5][0-9](:[0-5][0-9])?\s(AM|PM))))?)\ /\n$1\n/g;

[download]

The result is desirable when I using $1 but not $+...so I would like to ask, what is their different?

Thank you

In reply to Confusion of the effect of $+ and $1 by Anonymous Monk

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