perl - 動的リスト項目の識別

Question

コードが次のリストデータを特定しようとしています:

my $listdata = '
List Items:     
(1)LIST 1 data 
(a)sub data
(b)sub data
(c)sub data
(d)sub data
    (i)sub-sub data
    (ii)sub-sub data
        (A)sub-sub-sub data
        (B)sub-sub-sub data
    (iii)sub-sub data
(e)sub data
(2)LIST 2 data 
(3)LIST 3 data 
';

    #print "\n\n\n$listdata\n\n";

    ###Array of multi-level patterns 
    my @level_check =('\(\d+\)','(?<!\()\d+\)','\([a-h]\)','(?<!\()[a-h]\)','\([A-H]\)','(?<!\()[A-H]\)','\d+\.',
                      '\([IVX]+\)','(?<!\()[IVX]+\)','\([ivx]+\)','(?<!\()[ivx]+\)','\-');

    ###pattern for each levels
    my ($first_level,$second_level,$third_level,$fourth_level);

    ###First from each pattern
    my ($first_occur,$second_occur,$third_occur,$fourth_occur);

    #++++++++++++++++++++++++Pattern for multilevel list+++++++++++++++++++++++#
    my $pattern = '((?:[IVX\-\(\)\d\.\-][a-z]?\)?)+)';

    $listdata =~ s{$pattern}{
        my ($leveltemp) = ($1);
        $first_occur = $leveltemp if !$first_occur;

        #print "$data";
        #print "all_level: $leveltemp##\n";

        #########First Level Start
        for($i=0; $i<scalar(@level_check);$i++){
            if($first_occur =~ /^$level_check[$i]$/){
                $first_level = $level_check[$i] if !$first_level;
                #print "$level_check[$i] =>is Ist: $first_level\n";
            }
        }

        for($i=0; $i<scalar(@level_check);$i++){

            if($leveltemp =~ /^$first_level$/){
                $leveltemp =~ s{$pattern}{<<LIST1>>$2$3};
                #print"**$data level matched: $leveltemp => $first_level\n";
                ############First Level End
            }
            else
            {
                ######Second level Start
                if($leveltemp !~ /^(?:<<LIST\d+>>|\d{3,}\,?|\([a-h]{3,})/i){
                    $second_occur = $leveltemp if !$second_occur;
                    #print "$leveltemp :$second_occur\n";

                    for($i=0; $i<scalar(@level_check);$i++){
                        if($second_occur =~ /^$level_check[$i]$/){
                        $second_level = $level_check[$i] if !$second_level;
                        #print "$leveltemp =>is IInd: $second_level\n";
                        }
                    }

                    if($leveltemp =~ /^$second_level/){
                        $leveltemp =~ s{$pattern}{<<LIST2>>$2$3};
                        #print"**level matched: $leveltemp => $seconf_level\n";
                        ######Second level End
                    }
                    else
                    {
                        ########Third Level Start   
                        if($leveltemp !~ /^(?:<<LIST\d+>>|\d{3,}\,?|\([A-h]{3,})/i){
                            $third_occur = $leveltemp if !$third_occur;

                            for($i=0; $i<scalar(@level_check);$i++){
                                if($third_occur =~ /^$level_check[$i]$/){
                                    $third_level = $level_check[$i] if !$third_level;
                                    #print "$leveltemp =>is IIIrd: $third_level\n";
                                }
                            }

                            if($leveltemp =~ /^$third_level/){
                                $leveltemp =~ s{$pattern}{<<LIST3>>$2$3};
                                #print"**level matched: $leveltemp => $third_level\n";
                            #########Third Level End
                            }
                            else
                            {
                                ########Fourth Level Start  
                                if($leveltemp !~ /^(?:<<LIST+>>|\d{3,}\,?|\([A-z]{3,})/i){

                                    $fourth_occur = $leveltemp if !$fourth_occur;
                                        #print "$leveltemp :$fourth_occur\n";
                                    for($i=0; $i<scalar(@level_check);$i++){
                                        if($fourth_occur =~ /^$level_check[$i]$/){
                                            $fourth_level = $level_check[$i] if !$fourth_level;
                                            #print "$leveltemp =>is IVrth: $fourth_level\n";
                                        }
                                    }

                                    if($leveltemp =~ /^$fourth_level/){
                                        $leveltemp =~ s{$pattern}{<<LIST4>>$2$3};
                                        #print"**$fourth_occur  level matched: $leveltemp => $fourth_level\n";
                                        #########Fourth Level End
                                    }
                                    #######Add Next Levels Here If Any in else loop


                                }
                            }#IV lvl else loop end
                        }   
                    }#III lvl else loop end
                }
            }#IInd lvl else loop end

        }#Ist lvl for loop end

        "$leveltemp"
    }gsixe;

print "$listdata\n";

必要な出力:

 <<LIST1>>(1)LIST 1 data 
 <<LIST2>>(a)sub data
 <<LIST2>>(b)sub data
 <<LIST2>>(c)sub data
 <<LIST2>>(d)sub data
 <<LIST3>>(i)sub-sub data
 <<LIST3>>(ii)sub-sub data
 <<LIST4>>(A)sub-sub-sub data
 <<LIST4>>(B)sub-sub-sub data
 <<LIST3>>(iii)sub-sub data
 <<LIST2>>(e)sub data
 <<LIST1>>(2)LIST 2 data 
 <<LIST1>>(3)LIST 3 data

問題は、レベルごとにコードを入力する必要があることです。ここでは最大 4 つのレベルをコーディングしました。しかし、これは解決策ではありません (リストには任意の数のサブレベルがある場合があります)。リストのすべての可能なサブレベルをカバーする短いコードを記述する他の方法はありますか? 繰り返しますが、リストは動的です。リストは次のいずれかの形式で開始できます = A) (A) 1. 1) (1) a) (a) i) (i)。