There is no real difference. The substitution op can take nearly any character as delimiter. See perlop for the rules concerning that.

The reason your s/// fails is that you have an additional slash in the substitution string. Backwhack it (escape with \ ) to make that version work.

s/(^\d+[.]\s.+)/<h1>$1<\/h1>/g ;
#                      ^

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After Compline,
Zaxo

In reply to Re: s!!! vs. s/// by Zaxo
in thread s!!! vs. s/// by imlou

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