print keys %map_function 输出 散列的值： OK_funcsplit_funcpackage_VAR

my %map_function = (
     88     "OK_func" => "open_statement",
     89     "package_VAR" => "positional",
     90     "split_func" => "prototypes",
     91 );
     92 my @substr = keys %map_function;
     93 my @unpacking_list = values %map_function;
     94 print "@substr";
     95 print "\n"."@unpacking_list";
     96 print "\n";
     97 print "@unpacking_list\n";
     98 print keys %map_function

98行    print keys %map_function   输出： OK_funcsplit_funcpackage_VAR

如果是打印这个：   print my $sleep_func = keys %map_function

输出：　　　　　　3