* All operators are now strictly following the semantics we all know from

  C/C++.  I.e. e1+e2=42; is now impossible and other such stuff.  For all
  remaining errors (i.e. ++e1 = e1+1;) the compiler alone is to blame...

diff --git a/ginac/ex.cpp b/ginac/ex.cpp
index 77c7983300ed10edc670ea076be17a481be8e313..02d20e8894f1308e14850fced01d4cd43a8f0c68 100644 (file)
--- a/ginac/ex.cpp
+++ b/ginac/ex.cpp
@@ -199,25 +199,6 @@ ex ex::rhs(void) const
        return (*static_cast<relational *>(bp)).rhs();
 }
 
-/** Used internally by operator+() to add two ex objects together. */
-ex ex::exadd(const ex & rh) const
-{
-       return (new add(*this,rh))->setflag(status_flags::dynallocated);
-}
-
-/** Used internally by operator*() to multiply two ex objects together. */
-ex ex::exmul(const ex & rh) const
-{
-       // Check if we are constructing a mul object or a ncmul object.  Due to
-       // ncmul::eval()'s rule to pull out commutative elements we need to check
-       // only one of the elements.
-       if (rh.bp->return_type()==return_types::commutative ||
-           bp->return_type()==return_types::commutative)
-               return (new mul(*this,rh))->setflag(status_flags::dynallocated);
-       else
-               return (new ncmul(*this,rh))->setflag(status_flags::dynallocated);
-}
-
 // private
 
 /** Make this ex writable (if more than one ex handle the same basic) by 

diff --git a/ginac/ex.h b/ginac/ex.h
index 8ade899b06136f1479a982834547fae35503a3ba..7b36eff864bc061ee4e86e1efb0c3c48d0139f37 100644 (file)
--- a/ginac/ex.h
+++ b/ginac/ex.h
@@ -52,7 +52,7 @@ public:
        ex();
        ~ex();
        ex(const ex & other);
-       const ex & operator=(const ex & other);
+       ex & operator=(const ex & other);
        // other ctors
 public:
        ex(const basic & other);
@@ -124,9 +124,6 @@ public:
        unsigned return_type(void) const { return bp->return_type(); }
        unsigned return_type_tinfo(void) const { return bp->return_type_tinfo(); }
        unsigned gethash(void) const { return bp->gethash(); }
-       
-       ex exadd(const ex & rh) const;
-       ex exmul(const ex & rh) const;
 private:
        void construct_from_basic(const basic & other);
        void construct_from_int(int i);
@@ -212,16 +209,17 @@ ex::ex(const ex & other) : bp(other.bp)
 }
 
 inline
-const ex & ex::operator=(const ex & other)
+ex & ex::operator=(const ex & other)
 {
        /*debugmsg("ex operator=",LOGLEVEL_ASSIGNMENT);*/
        GINAC_ASSERT(bp!=0);
        GINAC_ASSERT(bp->flags & status_flags::dynallocated);
        GINAC_ASSERT(other.bp!=0);
        GINAC_ASSERT(other.bp->flags & status_flags::dynallocated);
+       // NB: must first increment other.bp->refcount, since other might be *this.
+       ++other.bp->refcount;
        if (--bp->refcount==0)
                delete bp;
-       ++other.bp->refcount;
        bp = other.bp;
 #ifdef OBSCURE_CINT_HACK
        update_last_created_or_assigned_bp();

diff --git a/ginac/operators.cpp b/ginac/operators.cpp
index ee240174f6ad0f5cac9a5daee41d69316e0ecb29..3a4229ba1dbb72e1535671e316fbd7a076079fea 100644 (file)
--- a/ginac/operators.cpp
+++ b/ginac/operators.cpp
@@ -22,7 +22,10 @@
 
 #include "operators.h"
 #include "numeric.h"
+#include "add.h"
+#include "mul.h"
 #include "power.h"
+#include "ncmul.h"
 #include "relational.h"
 #include "print.h"
 #include "debugmsg.h"
@@ -30,54 +33,79 @@
 
 namespace GiNaC {
 
+/** Used internally by operator+() to add two ex objects together. */
+static inline const ex exadd(const ex & lh, const ex & rh)
+{
+       return (new add(lh,rh))->setflag(status_flags::dynallocated);
+}
+
+/** Used internally by operator*() to multiply two ex objects together. */
+static inline const ex exmul(const ex & lh, const ex & rh)
+{
+       // Check if we are constructing a mul object or a ncmul object.  Due to
+       // ncmul::eval()'s rule to pull out commutative elements we need to check
+       // only one of the elements.
+       if (rh.return_type()==return_types::commutative ||
+           lh.return_type()==return_types::commutative)
+               return (new mul(lh,rh))->setflag(status_flags::dynallocated);
+       else
+               return (new ncmul(lh,rh))->setflag(status_flags::dynallocated);
+}
+
+/** Used internally by operator-() and friends to change the sign of an argument. */
+static inline const ex exminus(const ex & lh)
+{
+       return (new mul(lh,_ex_1()))->setflag(status_flags::dynallocated);
+}
+
 // binary arithmetic operators ex with ex
 
-ex operator+(const ex & lh, const ex & rh)
+const ex operator+(const ex & lh, const ex & rh)
 {
        debugmsg("operator+(ex,ex)",LOGLEVEL_OPERATOR);
-       return lh.exadd(rh);
+       return exadd(lh, rh);
 }
 
-ex operator-(const ex & lh, const ex & rh)
+const ex operator-(const ex & lh, const ex & rh)
 {
        debugmsg("operator-(ex,ex)",LOGLEVEL_OPERATOR);
-       return lh.exadd(rh.exmul(_ex_1()));
+       return exadd(lh, exminus(rh));
 }
 
-ex operator*(const ex & lh, const ex & rh)
+const ex operator*(const ex & lh, const ex & rh)
 {
        debugmsg("operator*(ex,ex)",LOGLEVEL_OPERATOR);
-       return lh.exmul(rh);
+       return exmul(lh, rh);
 }
 
-ex operator/(const ex & lh, const ex & rh)
+const ex operator/(const ex & lh, const ex & rh)
 {
        debugmsg("operator/(ex,ex)",LOGLEVEL_OPERATOR);
-       return lh.exmul(power(rh,_ex_1()));
+       return exmul(lh, power(rh,_ex_1()));
 }
 
 
 // binary arithmetic operators numeric with numeric
 
-numeric operator+(const numeric & lh, const numeric & rh)
+const numeric operator+(const numeric & lh, const numeric & rh)
 {
        debugmsg("operator+(numeric,numeric)",LOGLEVEL_OPERATOR);
        return lh.add(rh);
 }
 
-numeric operator-(const numeric & lh, const numeric & rh)
+const numeric operator-(const numeric & lh, const numeric & rh)
 {
        debugmsg("operator-(numeric,numeric)",LOGLEVEL_OPERATOR);
        return lh.sub(rh);
 }
 
-numeric operator*(const numeric & lh, const numeric & rh)
+const numeric operator*(const numeric & lh, const numeric & rh)
 {
        debugmsg("operator*(numeric,numeric)",LOGLEVEL_OPERATOR);
        return lh.mul(rh);
 }
 
-numeric operator/(const numeric & lh, const numeric & rh)
+const numeric operator/(const numeric & lh, const numeric & rh)
 {
        debugmsg("operator/(numeric,ex)",LOGLEVEL_OPERATOR);
        return lh.div(rh);
@@ -86,83 +114,125 @@ numeric operator/(const numeric & lh, const numeric & rh)
 
 // binary arithmetic assignment operators with ex
 
-const ex & operator+=(ex & lh, const ex & rh)
+ex & operator+=(ex & lh, const ex & rh)
 {
        debugmsg("operator+=(ex,ex)",LOGLEVEL_OPERATOR);
-       return (lh=lh.exadd(rh));
+       return lh = exadd(lh, rh);
 }
 
-const ex & operator-=(ex & lh, const ex & rh)
+ex & operator-=(ex & lh, const ex & rh)
 {
        debugmsg("operator-=(ex,ex)",LOGLEVEL_OPERATOR);
-       return (lh=lh.exadd(rh.exmul(_ex_1())));
+       return lh = exadd(lh, exminus(rh));
 }
 
-const ex & operator*=(ex & lh, const ex & rh)
+ex & operator*=(ex & lh, const ex & rh)
 {
        debugmsg("operator*=(ex,ex)",LOGLEVEL_OPERATOR);
-       return (lh=lh.exmul(rh));
+       return lh = exmul(lh, rh);
 }
 
-const ex & operator/=(ex & lh, const ex & rh)
+ex & operator/=(ex & lh, const ex & rh)
 {
        debugmsg("operator/=(ex,ex)",LOGLEVEL_OPERATOR);
-       return (lh=lh.exmul(power(rh,_ex_1())));
+       return lh = exmul(lh, power(rh,_ex_1()));
 }
 
 
 // binary arithmetic assignment operators with numeric
 
-const numeric & operator+=(numeric & lh, const numeric & rh)
+numeric & operator+=(numeric & lh, const numeric & rh)
 {
        debugmsg("operator+=(numeric,numeric)",LOGLEVEL_OPERATOR);
-       return (lh=lh.add(rh));
+       lh = lh.add(rh);
+       return lh;
 }
 
-const numeric & operator-=(numeric & lh, const numeric & rh)
+numeric & operator-=(numeric & lh, const numeric & rh)
 {
        debugmsg("operator-=(numeric,numeric)",LOGLEVEL_OPERATOR);
-       return (lh=lh.sub(rh));
+       lh = lh.sub(rh);
+       return lh;
 }
 
-const numeric & operator*=(numeric & lh, const numeric & rh)
+numeric & operator*=(numeric & lh, const numeric & rh)
 {
        debugmsg("operator*=(numeric,numeric)",LOGLEVEL_OPERATOR);
-       return (lh=lh.mul(rh));
+       lh = lh.mul(rh);
+       return lh;
 }
 
-const numeric & operator/=(numeric & lh, const numeric & rh)
+numeric & operator/=(numeric & lh, const numeric & rh)
 {
        debugmsg("operator/=(numeric,numeric)",LOGLEVEL_OPERATOR);
-       return (lh=lh.div(rh));
+       lh = lh.div(rh);
+       return lh;
 }
 
+
 // unary operators
 
-ex operator+(const ex & lh)
+const ex operator+(const ex & lh)
 {
        debugmsg("operator+(ex)",LOGLEVEL_OPERATOR);
        return lh;
 }
 
-ex operator-(const ex & lh)
+const ex operator-(const ex & lh)
 {
        debugmsg("operator-(ex)",LOGLEVEL_OPERATOR);
-       return lh.exmul(_ex_1());
+       return exminus(lh);
 }
 
-numeric operator+(const numeric & lh)
+const numeric operator+(const numeric & lh)
 {
        debugmsg("operator+(numeric)",LOGLEVEL_OPERATOR);
        return lh;
 }
 
-numeric operator-(const numeric & lh)
+const numeric operator-(const numeric & lh)
 {
        debugmsg("operator-(numeric)",LOGLEVEL_OPERATOR);
        return _num_1().mul(lh);
 }
 
+
+// increment / decrement operators
+
+/** Expression prefix increment.  Adds 1 and returns incremented ex. */
+ex & operator++(ex & rh)
+{
+       debugmsg("operator++(ex)",LOGLEVEL_OPERATOR);
+       return rh = exadd(rh, _ex1());
+}
+
+/** Expression prefix decrement.  Subtracts 1 and returns decremented ex. */
+ex & operator--(ex & rh)
+{
+       debugmsg("operator--(ex)",LOGLEVEL_OPERATOR);
+       return rh = exadd(rh, _ex_1());
+}
+
+/** Expression postfix increment.  Returns the ex and leaves the original
+ *  incremented by 1. */
+const ex operator++(ex & lh, int)
+{
+       debugmsg("operator++(ex,int)",LOGLEVEL_OPERATOR);
+       ex tmp(lh);
+       lh = exadd(lh, _ex1());
+       return tmp;
+}
+
+/** Expression Postfix decrement.  Returns the ex and leaves the original
+ *  decremented by 1. */
+const ex operator--(ex & lh, int)
+{
+       debugmsg("operator--(ex,int)",LOGLEVEL_OPERATOR);
+       ex tmp(lh);
+       lh = exadd(lh, _ex_1());
+       return tmp;
+}
+
 /** Numeric prefix increment.  Adds 1 and returns incremented number. */
 numeric& operator++(numeric & rh)
 {
@@ -181,7 +251,7 @@ numeric& operator--(numeric & rh)
 
 /** Numeric postfix increment.  Returns the number and leaves the original
  *  incremented by 1. */
-numeric operator++(numeric & lh, int)
+const numeric operator++(numeric & lh, int)
 {
        debugmsg("operator++(numeric,int)",LOGLEVEL_OPERATOR);
        numeric tmp(lh);
@@ -191,7 +261,7 @@ numeric operator++(numeric & lh, int)
 
 /** Numeric Postfix decrement.  Returns the number and leaves the original
  *  decremented by 1. */
-numeric operator--(numeric & lh, int)
+const numeric operator--(numeric & lh, int)
 {
        debugmsg("operator--(numeric,int)",LOGLEVEL_OPERATOR);
        numeric tmp(lh);

diff --git a/ginac/operators.h b/ginac/operators.h
index 47d1b745a3602aba91fda96b891cb337fc5ca5f2..b84d38b6eb85affb6b7a294b99b68f4ec389cc3f 100644 (file)
--- a/ginac/operators.h
+++ b/ginac/operators.h
@@ -32,39 +32,46 @@ class numeric;
 class relational;
 
 // binary arithmetic operators ex with ex
-ex operator+(const ex & lh, const ex & rh);
-ex operator-(const ex & lh, const ex & rh);
-ex operator*(const ex & lh, const ex & rh);
-ex operator/(const ex & lh, const ex & rh);
+const ex operator+(const ex & lh, const ex & rh);
+const ex operator-(const ex & lh, const ex & rh);
+const ex operator*(const ex & lh, const ex & rh);
+const ex operator/(const ex & lh, const ex & rh);
 
 // binary arithmetic operators numeric with numeric
-numeric operator+(const numeric & lh, const numeric & rh);
-numeric operator-(const numeric & lh, const numeric & rh);
-numeric operator*(const numeric & lh, const numeric & rh);
-numeric operator/(const numeric & lh, const numeric & rh);
+const numeric operator+(const numeric & lh, const numeric & rh);
+const numeric operator-(const numeric & lh, const numeric & rh);
+const numeric operator*(const numeric & lh, const numeric & rh);
+const numeric operator/(const numeric & lh, const numeric & rh);
 
 // binary arithmetic assignment operators with ex
-const ex & operator+=(ex & lh, const ex & rh);
-const ex & operator-=(ex & lh, const ex & rh);
-const ex & operator*=(ex & lh, const ex & rh);
-const ex & operator/=(ex & lh, const ex & rh);
+ex & operator+=(ex & lh, const ex & rh);
+ex & operator-=(ex & lh, const ex & rh);
+ex & operator*=(ex & lh, const ex & rh);
+ex & operator/=(ex & lh, const ex & rh);
 
 // binary arithmetic assignment operators with numeric
-const numeric & operator+=(numeric & lh, const numeric & rh);
-const numeric & operator-=(numeric & lh, const numeric & rh);
-const numeric & operator*=(numeric & lh, const numeric & rh);
-const numeric & operator/=(numeric & lh, const numeric & rh);
+numeric & operator+=(numeric & lh, const numeric & rh);
+numeric & operator-=(numeric & lh, const numeric & rh);
+numeric & operator*=(numeric & lh, const numeric & rh);
+numeric & operator/=(numeric & lh, const numeric & rh);
 
 // unary operators
-ex operator+(const ex & lh);
-ex operator-(const ex & lh);
+const ex operator+(const ex & lh);
+const ex operator-(const ex & lh);
+
+const numeric operator+(const numeric & lh);
+const numeric operator-(const numeric & lh);
+
+// increment / decrement operators
+ex & operator++(ex & rh);
+ex & operator--(ex & rh);
+const ex operator++(ex & lh, int);
+const ex operator--(ex & lh, int);
 
-numeric operator+(const numeric & lh);
-numeric operator-(const numeric & lh);
 numeric& operator++(numeric & rh);
 numeric& operator--(numeric & rh);
-numeric operator++(numeric & lh, int);
-numeric operator--(numeric & lh, int);
+const numeric operator++(numeric & lh, int);
+const numeric operator--(numeric & lh, int);
 
 // binary relational operators ex with ex
 relational operator==(const ex & lh, const ex & rh);