Hello all. I have been playing around with Per::Critic on the command line and found to my dismay that some of my modules do not pass gentle. I realize that I can ignore the recommendations of Perl critic, but I would love for my modules to pass "gentle" before I begin ignoring things.

The most common issue is that I modify $_ in list functions. The following is a convenient and short one liner to put the lines of files into a list. I thought doing it this way was nice and slim.

  my @list       = map { chomp($_); $_ } <$fh>;
  my @uc_list    = map { chomp $_; [uc $_] } <$lc_fh>; # used only onc
+e
  my @split_list = map { chomp $_; [ split(/\|/, $_) ] } <$piped_fh>; 
+# used only once
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In one subroutine, I have this three times.

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

  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;
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And my Fancy::Map modifies $_ too.

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};
}
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If this is something ignored usually, I will ignore it, but I would like to know how to make it better. Should I just assign $_ to a variable and then use the variable?

Another thing that I am confused by is why the expression form of eval is discouraged?

  if ($raw_value =~ /\*/) {    # multiplication
    $total_value = eval($raw_value);
    ($amount, $base_value) = split(/\*/,$raw_value);
  }
  elsif ($raw_value =~ /\//) { # division
    $base_value = eval($raw_value);
    ($total_value, $amount) = split(/\//, $raw_value);
  }
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The rest of the gentle issues are me being lazy with conditionals. While writing I was thinking my $var = "foo" if 'some condition', but Perl critic does not like it, but it is fixed easily.

NOTE: Please see my update. Most are fixed, but the eval problem remains.