Export replace_desc_numbers_by_descs from graph_copy_with_names

Libraries/graph_copy/graph_copy_with_names.dcl

@@ -8,4 +8,6 @@ from symbols_in_program import ::Symbol;
 copy_to_string_with_names :: a -> (!*{#Char},!*{#DescInfo},!*{#String});
 copy_from_string_with_names :: !*{#Char} !*{#DescInfo} !*{#String} !{#Symbol} -> (.a,!Int);
 
+// Internal functions (normally you should not use them directly):
+replace_desc_numbers_by_descs :: !Int !*{#Char} !{#Int} !Int !Int -> *{#Char};
 make_symbol_name :: !String !String !Int -> String;