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

[ginac.git] / ginac / operators.cpp

diff --git a/ginac/operators.cpp b/ginac/operators.cpp
index bd9a4425b4534cd85fff4c5d1d23e4d9aba29317..3a4229ba1dbb72e1535671e316fbd7a076079fea 100644 (file)
--- a/ginac/operators.cpp
+++ b/ginac/operators.cpp
@@ -22,61 +22,90 @@
 
 #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"
 #include "utils.h"
 
 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);
@@ -85,83 +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)
 {
@@ -180,7 +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);
@@ -190,7 +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);
@@ -240,7 +311,7 @@ relational operator>=(const ex & lh, const ex & rh)
 
 std::ostream & operator<<(std::ostream & os, const ex & e)
 {
-       e.print(os);
+       e.print(print_context(os));
        return os;
 }