Allow user defined functions to be parsed.

[ginac.git] / ginac / parser / parse_context.h

diff --git a/ginac/parser/parse_context.h b/ginac/parser/parse_context.h
index 3516320981c1b82191c404361d6086e4a6cd96f6..81b2cd15a9ada239ae9c2e55efaa32fce66a455f 100644 (file)
--- a/ginac/parser/parse_context.h
+++ b/ginac/parser/parse_context.h
@@ -82,6 +82,11 @@ typedef ex (*reader_func)(const exvector& args);
  *    number of arguments.
  * 3. User can extend the parser via custom prototype tables. It's possible
  *    to read user defined classes, create abbreviations, etc.
+ *
+ * NOTE: due to a hack that allows user defined functions to be parsed, the map
+ *       value of type reader_func is internally treated as an unsigned and not as a
+ *       function pointer!! The unsigned has to correspond to the serial number of
+ *       the defined GiNaC function.
  */
 typedef std::map<prototype, reader_func> prototype_table;