Hmm.. Just tried: 
$_ = "1.2.a.b";
s/(?!\d[.,]\d)([^\w\s])(?!\s)/$1 /g;
print;

[download]
Prints "1. 2. a. b"

--dda

In reply to Re: Re: Regex to add space after punctuation sign by dda
in thread Regex to add space after punctuation sign by dda

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