I thought I was OK with basic regular expressions, but the behaviour of this has bamboozled me...

Can you please explain what I am doing wrong?

perl -e "my $test = join ', ', ('A', 'B', 'C');$test =~ s/,(.+?)$/ and
+$1/; print $test;"

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The result I want is for the list to have a comma separating each item except the last two items which will be separated by 'and'. So the results should be along these lines:
A -> A
A, B -> A and B
A, B, C -> A, B and C

However, the result of the one liner above is A and B, C

I expected ,(.+?)$ to match a comma followed by the shortest possible text and the end of the string. I expected (.+?) to match ' C' as that is the shortest possible match and ? is used to make the match non-greedy

In reply to Non-greedy substitution by Bod

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