Turn attach into a function that stores the data internally and can do the checking. 
{
   my %store = ();

sub attach
{
   my ($type, $value) = @_;
   if ($value)
   {
      $store{$type} = $value};
   }
   else
   {
      my $default = "height=19 width=15 src='/images/attach/UNKNOWN.gi
+f' border=0";
      return $store{$type} if $store{$type};
      $default =~ s/UNKNOWN/$type/;
      return $default;
   }
}
}

# Now, call 
attach('file',"height=19 width=15 src='/images/attach/file.gif' border
+=0");
attach('URL',"height=19 width=15 src='/images/attach/URL.gif' border=0
+");
# to initialise, and 
attach($mime_type);
# to access

[download]
If you want to objectise it, make attach a method of the {image} object.

Or, hide the function part by using Tie::Hash and tweaking the FETCH function to provide a default.
--
Brovnik

In reply to Re: Method autovivification with variable values? by Brovnik
in thread Method autovivification with variable values? by tame1

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