As an alternative to the above, you could do something like...

my @patterns = ("field", "f.i.e.l.d", "the");
my $str = "There are many soccer fields in England - f1i2e3l4d f1i2e3l
+4d";

my %matches = map { $_ => [ $str =~ /$_/g ] } @patterns;
__END__
{
  "f.i.e.l.d" => ["f1i2e3l4d", "f1i2e3l4d"],
  field => ["field"],
  the => [],
}
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