delete function for php file

deleteFuncForPHP.pl

#!/usr/bin/env perl
use feature 'say';
use Carp (carp,croak);
use IO::File;

sub del_lines($$);
croak "Usage: file" unless  @ARGV ==1;
my $file = shift;
my $fh = IO::File->new($file,'r');
my $fail = IO::File->new("$file.del_fail",'w');
my $total=0;
while(!$fh->eof) {
     chomp(my $line = $fh->getline());
     my($file,$func) = split /\s+/, $line;
     my $code = del_lines($file, $func);
     if($code == 1) {
        say "del function $file $func finished";
     }else{
        $fail->print("del function $file $func fail\n");
     }
}
$fh->close;
$fail->close;

sub del_lines($$) {
    my($file, $func) = @_;
    my $f = IO::File->new($file,'r');
    my $bak = IO::File->new("$file.bak",'w');
    $bak->autoflush;
    my $flag = 0;
    my $line_no = 0;
    my $branch_num = 0;
    my @comment;
    my $comment_flag = 0;
    while(!$f->eof) {
       chomp(my $line = $f->getline());
       if($flag == 0) {
               if ($line =~ /^\s*\/\// ) {
                  push @comment, $line;
                  next;
               }
               if($line =~ /^\s*\/\*/ && $line =~ /\*\/\s*$/) {
                    push @comment, $line;
                    next;
               }
               if ($line =~ /^\s*\/\*/) {
                  $comment_flag = 1;
                  push @comment, $line;
                  next;
               }
               if($comment_flag == 1 && $line !~ /\*\//) {
                   push @comment, $line;
                   next;
               }
               if ($line =~ /\*\//) {
                    $comment_flag =  0;
                    push @comment, $line;
                    next;
               }
       }
       if ( $line =~ /\s+$func\s*\(/ && $line =~ /function/) { #当前行 
            $flag = 1;
            @comment = ();
       }
       if ($line !~ /^\s*$/ && $flag == 0) {
           if(@comment) {
               foreach(@comment) {
                  $bak->write("$_\n");   
               }
           }
           $bak->write("$line\n");
           @comment = ();
           next;
       } elsif ( $flag == 0 ) {
            push @comment, $line;
            next;
       }
       if($line =~ /^\s*\/\//) {
            next;
       }
       #say "flag=$flag line_no=$line_no branch_num=$branch_num line=$line";
       $line_no += 1;
       if(my $n=()=$line =~ /\{/g) {
           $branch_num+=$n;
       }
       if(my $n = () = $line =~ /\}/g) {
           $branch_num-=$n; 
           if ( $flag ==1  && $branch_num == 0) {
               $flag=0;
               next;
           }
        }
     }
     $f->close;
     $bak->flush && $bak->close;
     my $cmd = qq/php -l $file.bak/;
     $cmd=qx[$cmd];      
     if($cmd =~ /No\ssyntax\serrors/) {
         rename("$file.bak",$file);   
         return 1;
     }
     return 0;
}
__COMMENT__
file format
/path/to/models/tools/trafficData.php _getAllCities