If you, say, writing a ‘ls’ subroutine and write down something like this:
sub ls{
my ($pattern)=@_;
for my $f (glob $pattern){
print "$f\n";
}
}
If you do
ls "*.txt"
This works, but if you
ls "index.txt"
It always shows “index.txt”, no matter whether “index.txt” exists or not.
This is actually an expected behavior. Consider typing following commands in shell.
gedit *.txt
gedit index.txt
For first one, shell passes all .txt file in current directory to gedit. For second one, shell should pass ‘index.txt’ to gedit, it’s up to gedit to determine what to do with if index.txt does not exist.
So for ‘ls’ like function, following are better:
sub ls{
my ($pattern)=@_;
for my $f (glob $pattern){
if ( -e $f){
print "$f\n";
}
}
}