if(eval { require "foo.pm"; 1; } ) {
   print "loaded module ok\n";
}else{
   print "could not load module $@\n";
}

##</code><code>##

if(eval " use foo; 1" ) {
   print "loaded module ok\n";
}else{
   print "could not load module $@\n";
}

##</code><code>##

print petrol "hello there !";

##</code><code>##

print STDOUT "hello\n";

##</code><code>##

Unquoted string "petrol" may clash with future reserved word at p line 3.
Name "main::petrol" used only once: possible typo at p line 3.
print() on unopened filehandle petrol at p line 3.