my @list       = map { chomp($_); $_ } <$fh>;
  my @uc_list    = map { chomp $_; [uc $_] } <$lc_fh>; # used only once
  my @split_list = map { chomp $_; [ split(/\|/, $_) ] } <$piped_fh>; # used only once

##</code><code>##

  my @list       = map { chomp; $_ } <$fh>;
  my @uc_list    = map { chomp; [uc $_] } <$lc_fh>; # used only once
  my @split_list = map { chomp; [ split(/\|/, $_) ] } <$piped_fh>; # used only once

##</code><code>##

  my @array = map {
    $_ =~ s/^[\*\+-] (.+)/$1/;
    some_sub($_, $opt);
  } @another_array;

##</code><code>##

<code>
  my @array = map {
    some_sub($_, $opt);
  } @another_array;

##</code><code>##

  my @ids = map {
    $_ =~ s/<.+?>//g;
    $_ =~ s/^(\d+([stnrdh]{2}|))/NUMWORDS($1)/e;
    $_ =~ s/(.)\.\w{2,5}?$/$1/;
    $_ =~ s/&amp/and/g;
    $_ =~ s/&/and/g;
    $_ =~ s/Æ/Ae/g;
    $_ =~ s/Ç/C/g;
    $_ =~ s/Ü/U/g;
    $_ =~ s/(è|é|ê)/e/g;
    $_ =~ s/#/No/g;
    $_ =~ s/ /_/g;
    $_ =~ s/[^\w:.\-]//g;
    $_;
  } grep {defined($_)} @base;

##</code><code>##

  my @ids = map {
       s/<.+?>//gr
    =~ s/^(\d+([stnrdh]{2}|))/NUMWORDS($1)/er
    =~ s/(.)\.\w{2,5}?$/$1/r
    =~ s/&amp/and/gr
    =~ s/&/and/gr
    =~ s/Æ/Ae/gr
    =~ s/Ç/C/gr
    =~ s/Ü/U/gr
    =~ s/(è|é|ê)/e/gr
    =~ s/#/No/gr
    =~ s/ /_/gr
    =~ s/[^\w:.\-]//gr
  } grep { defined } @base;

##</code><code>##

sub fancy_map {
  my ($opt, $list) = @_;
  map {
    if (ref($_)) {
      fancy_map($opt, $_);
    }
    else {
      my $before = $opt->{'before'} ? $opt->{'before'}.' ' : '';
      my $after  = $opt->{'after'}  ? ' '.$opt->{'after'}  : '';
      $_ = $before.$_.$after;
    }
  } @{$list};
}

##</code><code>##

sub fancy_map {
  my ($opt, $list) = @_;
  map { ref $_
    ? fancy_map ($opt, $_)
    : do {
        my $before = $opt->{'before'} ?     $opt->{'before'}.' ' : '';
        my $after  = $opt->{'after'}  ? ' '.$opt->{'after'}      : '';
        $before.$_.$after;
      }
  } @{$list};
}