Perl CGI. Can I be sure of the order of <style> tags I use?

If I create two style strings, like so

my $style =<<'EOF';  
<-- @import url("foo.css"); -->  
EOF  

my $style2 =<<'EOF';  
<-- #thing_in_foo.css_that_I_want_to_override a {attributes;} -->  
EOF  

And I wish to include them in start_html like so:

print $q->start开发者_JAVA技巧_html({  
  -style => [
             {-code=>$style},  
             {-code=>$style2}
]);  

Or some such.

The long-term goal is to subclass the CGI module with a mess of defaults. I want to let the user pass some additional hash references to the object, like so:

my $q = subCGI->new({-code=>$style2});

The object will within build the start_html parameters, and I'd like to put that hash reference into the -style array. I plan to have some already in there; the intent is to have the user pass any css in the new() parameter such that it will cascade over the defaults.

I hope that makes sense.

Any subsequent additions to a hash using the same key as used previously will always overwrite the first. That is,

my %hash = (
     key => "value 1",
     key => "value 2",
);

...will always yield a key with value "value 2", never "value 1".

It is a somewhat common technique to use this to allow optional overrides, e.g.:

sub wrapper_around_something_common
{
     # get optional options from the caller
     my %options = @_;

     some_other_function(
         key_1 => 'some default',
         key_2 => 'another default',
         %options,      # and override with any options provided by user
     )
}