It's kind of a pain in the butt, but here's one way: 

my $haystack = "foobar";
my $needle = "Bar";

$haystack =~ /($needle)/gi;
print ((pos $haystack) - (length $needle));

[download]

In reply to Re: Answer: How can I find the first position of a substring case-insensitively? by cogent
in thread How can I find the first position of a substring case-insensitively? by ChilliHead

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