Enhance runtime error messages so they show the absolute line number

in the macro definition file where the error occurs.  Developers
should be able to jump to that line in the file and reach the
offending code.

lib/POE/Preprocessor.pm

@@ -9,7 +9,8 @@ use Filter::Util::Call;
 sub MAC_PARAMETERS () { 0 }
 sub MAC_CODE       () { 1 }
 sub MAC_NAME       () { 2 } # only used in temporary %macro
-sub MAC_LINE       () { 3 } # only used in temporary %macro
+sub MAC_FILE       () { 3 }
+sub MAC_LINE       () { 4 } # only used in temporary %macro
 
 sub STATE_PLAIN     () { 0x0000 }
 sub STATE_MACRO_DEF () { 0x0001 }
@@ -421,6 +422,7 @@ sub import {
               [ \@macro_params, # MAC_PARAMETERS
                 '',             # MAC_CODE
                 $macro_name,    # MAC_NAME
+                $file_name,     # MAC_FILE
                 $line_number,   # MAC_LINE
               ];
 
@@ -459,6 +461,8 @@ sub import {
 
               # Build a new bit of code here.
               my $substitution = $macros{$package_name}->{$name}->[MAC_CODE];
+              my $macro_file   = $macros{$package_name}->{$name}->[MAC_FILE];
+              my $macro_line   = $macros{$package_name}->{$name}->[MAC_LINE];
 
               foreach my $mac_param (@mac_params) {
                 my $use_param = shift @use_params;
@@ -471,7 +475,8 @@ sub import {
                 while ($sub_line--) {
                   splice( @sub_lines, $sub_line, 0,
                           "# line $line_number " .
-                          "\"macro $name (line $sub_line) " .
+                          "\"macro $name (defined in $macro_file at line " .
+                          ($macro_line + $sub_line + 1) . ") " .
                           "invoked from $file_name\""
                         );
                 }