List::MoreUtils is implemented in C and might give a modest performance advantage.

#!/usr/bin/perl -w

use List::MoreUtils;

my @foo=('a','b','c', 'd', 'e', 'f', 'g', 'h', 'i');

my $index = List::MoreUtils::first_index {$_ eq 'g'} @foo;

print ("G's index = $index\n");
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