X-Git-Url: https://www.ginac.de/ginac.git//ginac.git?p=ginac.git;a=blobdiff_plain;f=ginac%2Fexpair.h;h=2610e8fa47e3e0ec3e4fa3525aeb46f6cf54084f;hp=2f34b4b8795afc17f40526f2c7709d7f6deb049b;hb=eefedc70f63222beca918a3df89cabac700df1eb;hpb=4e3a4ac2bcb0837611ea31bc8fc05d84a20c33ac

diff --git a/ginac/expair.h b/ginac/expair.h
index 2f34b4b8..2610e8fa 100644
--- a/ginac/expair.h
+++ b/ginac/expair.h
@@ -3,7 +3,7 @@
  *  Definition of expression pairs (building blocks of expairseq). */
 
 /*
- *  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
@@ -25,6 +25,7 @@
 
 #include "ex.h"
 #include "numeric.h"
+#include "print.h"
 
 namespace GiNaC {
 
@@ -37,24 +38,11 @@ class expair
 {
 public:
 	expair() : rest(0), coeff(1) { }
-	~expair() { }
-	expair(const expair & other) : rest(other.rest), coeff(other.coeff)
-	{
-		GINAC_ASSERT(is_ex_exactly_of_type(coeff,numeric));
-	}
-	const expair & operator=(const expair & other)
-	{
-		if (this != &other) {
-			rest = other.rest;
-			coeff = other.coeff;
-		}
-		return *this;
-	}
-	
+
 	/** Construct an expair from two ex. */
 	expair(const ex & r, const ex & c) : rest(r), coeff(c)
 	{
-		GINAC_ASSERT(is_ex_exactly_of_type(coeff,numeric));
+		GINAC_ASSERT(is_exactly_a<numeric>(coeff));
 	}
 	
 	/** Member-wise check for canonical ordering equality. */
@@ -81,22 +69,20 @@ public:
 			return coeff.compare(other.coeff);
 	}
 	
-	/** Output to ostream in ugly raw format. */
-	void printraw(std::ostream & os) const
-	{
-		os << "expair(";
-		rest.printraw(os);
-		os << ",";
-		coeff.printraw(os);
-		os << ")";
-	}
+	void print(std::ostream & os) const;
 	
 	/** True if this is of the form (numeric,ex(1)). */
-	bool is_canonical_numeric(void) const
+	bool is_canonical_numeric() const
+	{
+		GINAC_ASSERT(is_exactly_a<numeric>(coeff));
+		return (is_exactly_a<numeric>(rest) && (coeff.is_equal(1)));
+	}
+
+	/** Swap contents with other expair. */
+	void swap(expair & other)
 	{
-		GINAC_ASSERT(is_ex_exactly_of_type(coeff,numeric));
-		return (is_ex_exactly_of_type(rest,numeric) &&
-		        (coeff.is_equal(1)));
+		rest.swap(other.rest);
+		coeff.swap(other.coeff);
 	}
 	
 	ex rest;    ///< first member of pair, an arbitrary expression
@@ -104,15 +90,29 @@ public:
 };
 
 /** Function object for insertion into third argument of STL's sort() etc. */
-class expair_is_less
-{
-public:
-	bool operator()(const expair &lh, const expair &rh) const
-	{
-		return lh.is_less(rh);
-	}
+struct expair_is_less : public std::binary_function<expair, expair, bool> {
+	bool operator()(const expair &lh, const expair &rh) const { return lh.is_less(rh); }
+};
+
+/** Function object not caring about the numerical coefficients for insertion
+ *  into third argument of STL's sort().  Note that this does not define a
+ *  strict weak ordering since for any symbol x we have neither 3*x<2*x or
+ *  2*x<3*x.  Handle with care! */
+struct expair_rest_is_less : public std::binary_function<expair, expair, bool> {
+	bool operator()(const expair &lh, const expair &rh) const { return (lh.rest.compare(rh.rest)<0); }
+};
+
+struct expair_swap : public std::binary_function<expair, expair, void> {
+	void operator()(expair &lh, expair &rh) const { lh.swap(rh); }
 };
 
+inline void swap(expair & e1, expair & e2)
+{ e1.swap(e2); }
+
+// This makes STL algorithms use the more efficient swap operation for ex objects
+inline void iter_swap(std::vector<expair>::iterator i1, std::vector<expair>::iterator i2)
+{ i1->swap(*i2); }
+
 } // namespace GiNaC
 
 #endif // ndef __GINAC_EXPAIR_H__