Two methods. 
print "OK" if m((?i:var)=/bin);

[download]
and 
my $m_var = qr/var/i;
print "OK" if m($m_var=/bin);

[download]
The first is faster for building one RE. The second if you need a series of them.

In reply to Re (tilly) 1: RegExps that are only partly case-insensitive by tilly
in thread RegExps that are only partly case-insensitive by dcorbin

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