Just quotemeta the search string then substitute any characters that you want to use as wildcards. I have used * and ?

#! /usr/bin/perl -w

use strict;
use warnings;

$/ = undef; my $text = <DATA>;

my $count = 1;
my $searchRegex = quotemeta $ARGV[0];;
$searchRegex =~ s/\\\*/\\S*/g;
$searchRegex =~ s/\\\?/\\S{1}/g;

print "Search RegEx = $searchRegex\n";
$text =~ s/($searchRegex)\b/print $count++, " $1\n"/ige;

__DATA__
can't won't
This is a selection of example passages to find
We received an invitation from Mark to his party
He provided information on how to get to his house.
He has been in the isolation ward for much of the year
due to some unfortunate bladder InFlaTiOn.
Let's hope he gets better!
IATION
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