my @reg_exes = (
  q|Reach Holly Smith for help by sending an email\nto hollysmith@nosuchdomain\.com\.|,
  q|For more information, contact Holly Smith at\nhollysmith@nosuchdomain\.com\.|,
  q|For more information, contact Holly Smith at \(800\) 555-1212 or\nvia email to hollysmith@nosuchdomain\.com|,
);

my $new_string = 'For more information, contact Holly Smith.';

# Then, after creating a list of eligible files in a particular directory 
# and then opening each file to slurp its contents into $slurped file 
# (code not shown here)...

for my $reg_ex ( @reg_exes ) {
    if ( $slurped_file =~ s/$reg_ex/$new_string/g ) {
        print "Matched one or more occurrences of reg ex '$reg_ex' and substituted '$new_string' each time\n";
    }
}

# Then store the changed file, etc.

##</code><code>##

my @patterns = (
  q|Reach Holly Smith for help by sending an email\nto hollysmith@nosuchdomain\.com\.|,
  q|For more information, contact Holly Smith at\nhollysmith@nosuchdomain\.com\.|,
  q|For more information, contact Holly Smith at \(800\) 555-1212 or\nvia email to hollysmith@nosuchdomain\.com|,
);

my @reg_exes;
for my $pat ( @patterns ) {
  push @reg_exes, qr/$pat/;
}

my $new_string = 'For more information, contact Holly Smith.';

# Then, after creating a list of eligible files in a particular directory 
# and then opening each file to slurp its contents into $slurped file 
# (code not shown here)...

for my $reg_ex ( @reg_exes ) {
    if ( $slurped_file =~ s/$reg_ex/$new_string/g ) {
        print "Matched one or more occurrences of reg ex '$reg_ex' and substituted '$new_string' each time\n";
    }
}

# Then store the changed file, etc.