Allow assigning variables refering to aggregates

Rakefile

@@ -38,6 +38,7 @@ desc 'Convert previous stage language into the current stage language'
 task :convert do
   File.open('boot/stage22/cl.elna', 'w') do |current_stage|
     seen_proc = false
+    seen_global_var = false
     File.readlines('boot/stage21/cl.elna').each do |line|
       seen_proc = true if line.start_with? 'proc'
       seen_proc = false if line.start_with? 'end'
@@ -46,7 +47,6 @@ task :convert do
 
           proc f();
           var
-          	x: ElnaLocation;
           	y: ElnaLocation;
           begin
           	y.line := 1;
@@ -58,6 +58,11 @@ task :convert do
           begin
           	f();
         FUN
+      elsif line.start_with?('var') && !seen_global_var
+        current_stage << <<~FUN
+          var
+          	x: ElnaLocation;
+        FUN
       else
         current_stage << line
       end