Splitting and printing with Perl - perl

Question

My Perl script is attempting to take in a command line argument that is a file name such as name.txt or hello.txt.exe and parse out the file extension based on the . delimiter, and print only the extension like exe or txt. Here's what I currently have which doesn't print anything and I'm not entirely sure why.
usr/bin/perl -w
use strict;
my ($user_arg) = shift #ARGV;
my ($ext);
if ( ($ext) = $user_arg =~ /(\.[^.].+)$/)
{
print "Ends in ", ($ext) = $user_arg =~ /(\.[^.].+)$/ , "\n";
print "Ends in" , ($ext) = $user_arg =~ /(\.[^.]+)$/, "\n";
}
elsif( ($ext) = $user_arg =~ /(\.[^.]+)$/)
{
print"Ends in " , ($ext), "\n";
}
else
{
print "No Extension";
}
*Updated, now my problem is the first statement will print both conditions if it's something like name.txt it will print .txt twice, where I want it to only print .txt once UNLESS it's name.txt.exe where I'd like it to print .txt.exe then .exe

Answer 1

There's two main issues here:
1) You need to shift off #ARGV
my $arg = shift #ARGV;
2) You need to escape the 'dot'
my #values = split /\./, $user_arg;
Other things...
You usually want to sanitize user input:
die "usage: $0 filename\n" if {some condition}
I think you mean chomp $val; in your foreach.
It wouldn't hurt to be familiar with File::Basename, fileparse could make your life easier. Although it might be overkill here.
UPDATE
You should be able to integrate this yourself. In your case you won't need to loop
over a list of files, you'll just have one.
This doesn't do what you want where it prints "txt.exe", "exe". But you can fine tune this to your liking.
my #file_tests = qw(nosuffix testfile.txt /path/to/file.exe foo.bar.baz);
for my $fullname (#file_tests) {
my #names = split /\./, $fullname;
# shift off the first element, which will
# give you the list of suffixs or an empty list
shift #names;
# you can decide how you want to print this list
# if scalar #names is 0 don't print anything
print "list of suffixes: " . join( ', ', #names ) . "\n"
if scalar(#names) > 0;
}
OUTPUT:
list of suffixes: txt
list of suffixes: exe
list of suffixes: bar, baz