if (not -e "$vundleDir"){
die "Vundle directory not exists, abort.\n";
} elsif (-s "$vundleDir") {
if (not -e "$vundleDir"){
die "Vundle directory not exists, abort.\n";
} elsif (-s "$vundleDir") {
print " clone submodules \n";
chdir $vundleDir;
! system "git submodule init" or die $!;
! system "git submodule update" or die $!;
print " clone submodules \n";
chdir $vundleDir;
! system "git submodule init" or die $!;
! system "git submodule update" or die $!;