dummy index renamer ignores index dimensions

[ginac.git] / ginac / ex.h

diff --git a/ginac/ex.h b/ginac/ex.h
index 0bbe12995148187102e48db52e3136de7a6835ee..14cfd5b54eb1f1ae8b6c3561bdd81a6520954ff2 100644 (file)
--- a/ginac/ex.h
+++ b/ginac/ex.h
@@ -3,7 +3,7 @@
  *  Interface to GiNaC's light-weight expression handles. */
 
 /*
- *  GiNaC Copyright (C) 1999-2001 Johannes Gutenberg University Mainz, Germany
+ *  GiNaC Copyright (C) 1999-2003 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
@@ -89,15 +89,28 @@ public:
        ex(long i);
        ex(unsigned long i);
        ex(double const d);
+
        /** Construct ex from string and a list of symbols. The input grammar is
-        *  similar to the GiNaC output format. All symbols to be used in the
-        *  expression must be specified in a lst in the second argument. Undefined
-        *  symbols and other parser errors will throw an exception. */
+        *  similar to the GiNaC output format. All symbols and indices to be used
+        *  in the expression must be specified in a lst in the second argument.
+        *  Undefined symbols and other parser errors will throw an exception. */
        ex(const std::string &s, const ex &l);
        
        // non-virtual functions in this class
 public:
-       void swap(ex & other);
+       /** Efficiently swap the contents of two expressions. */
+       void swap(ex & other)
+       {
+               GINAC_ASSERT(bp!=0);
+               GINAC_ASSERT(bp->flags & status_flags::dynallocated);
+               GINAC_ASSERT(other.bp!=0);
+               GINAC_ASSERT(other.bp->flags & status_flags::dynallocated);
+       
+               basic * tmpbp = bp;
+               bp = other.bp;
+               other.bp = tmpbp;
+       }
+
        void print(const print_context & c, unsigned level = 0) const;
        void printtree(std::ostream & os) const;
        void dbgprint(void) const;
@@ -344,6 +357,11 @@ bool ex::is_equal(const ex & other) const
 
 
 // utility functions
+
+/** Compare two objects of class quickly without doing a deep tree traversal.
+ *  @return "true" if they are equal
+ *          "false" if equality cannot be established quickly (e1 and e2 may
+ *          still be equal, in this case. */
 inline bool are_ex_trivially_equal(const ex &e1, const ex &e2)
 {
        return e1.bp == e2.bp;
@@ -452,6 +470,10 @@ inline bool is_zero(const ex & thisex)
 inline void swap(ex & e1, ex & e2)
 { e1.swap(e2); }
 
+// This makes STL algorithms use the more efficient swap operation for ex objects
+inline void iter_swap(std::vector<ex>::iterator i1, std::vector<ex>::iterator i2)
+{ i1->swap(*i2); }
+
 
 /* Function objects for STL sort() etc. */
 struct ex_is_less : public std::binary_function<ex, ex, bool> {
@@ -462,6 +484,10 @@ struct ex_is_equal : public std::binary_function<ex, ex, bool> {
        bool operator() (const ex &lh, const ex &rh) const { return lh.is_equal(rh); }
 };
 
+struct op0_is_equal : public std::binary_function<ex, ex, bool> {
+       bool operator() (const ex &lh, const ex &rh) const { return lh.op(0).is_equal(rh.op(0)); }
+};
+
 struct ex_swap : public std::binary_function<ex, ex, void> {
        void operator() (ex &lh, ex &rh) const { lh.swap(rh); }
 };