the input parser now handles (simple) indexed objects; the indices to be used

[ginac.git] / ginac / input_lexer.ll

diff --git a/ginac/input_lexer.ll b/ginac/input_lexer.ll
index f39de456a20a312b32148e9d4aea7df221488c56..4a5a65015e31ac983b64a92a18b1e8fb7457f694 100644 (file)
--- a/ginac/input_lexer.ll
+++ b/ginac/input_lexer.ll
@@ -4,7 +4,7 @@
  *  This file must be processed with flex. */
 
 /*
- *  GiNaC Copyright (C) 1999-2001 Johannes Gutenberg University Mainz, Germany
+ *  GiNaC Copyright (C) 1999-2002 Johannes Gutenberg University Mainz, Germany
  *
  *  This program is free software; you can redistribute it and/or modify
  *  it under the terms of the GNU General Public License as published by
@@ -38,6 +38,8 @@
 #include "fail.h"
 #include "numeric.h"
 #include "symbol.h"
+#include "lst.h"
+#include "idx.h"
 
 using namespace GiNaC;
 namespace GiNaC {
@@ -46,7 +48,7 @@ namespace GiNaC {
 
 } // namespace GiNaC
 
-// Table of all used symbols
+// Table of all used symbols/indices
 struct sym_def {
        sym_def() : predefined(false) {}
        sym_def(const ex &s, bool predef) : sym(s), predefined(predef) {}
@@ -165,22 +167,34 @@ void set_lexer_string(const std::string &s)
        curr_pos = 0;
 }
 
-// Set the list of predefined symbols
+// Get name of symbol/index
+std::string get_symbol_name(const ex & s)
+{
+       if (is_a<symbol>(s))
+               return ex_to<symbol>(s).get_name();
+       else if (is_a<idx>(s) && is_a<symbol>(s.op(0)))
+               return ex_to<symbol>(s.op(0)).get_name();
+       else
+               throw (std::runtime_error("get_symbol_name(): unexpected expression type"));
+}
+
+// Set the list of predefined symbols/indices
 void set_lexer_symbols(ex l)
 {
        syms.clear();
-       if (!is_ex_exactly_of_type(l, lst))
+       if (!is_exactly_a<lst>(l))
                return;
        for (unsigned i=0; i<l.nops(); i++) {
-               if (is_ex_exactly_of_type(l.op(i), symbol))
-                       syms[ex_to_symbol(l.op(i)).get_name()] = sym_def(l.op(i), true);
+               const ex &o = l.op(i);
+               if (is_a<symbol>(o) || (is_a<idx>(o) && is_a<symbol>(o.op(0))))
+                       syms[get_symbol_name(o)] = sym_def(o, true);
        }
 }
 
-// Check whether symbol was predefined
+// Check whether symbol/index was predefined
 bool is_lexer_symbol_predefined(const ex &s)
 {
-       sym_tab::const_iterator i = syms.find(ex_to_symbol(s).get_name());
+       sym_tab::const_iterator i = syms.find(get_symbol_name(s));
        if (i == syms.end())
                return false;
        else