comparer.h File Reference

Declarations for Comparer objects. More...

Go to the source code of this file.

Classes
class	ogdf::StdComparer< E >
	Standard comparer (valid as a static comparer). More...
class	ogdf::StdComparer< bool >
	Generates a specialization of the standard static comparer for booleans. More...
class	ogdf::TargetComparer< CONTENTTYPE, STATICCONTENTCOMPARER >
	A static comparer which compares the target of pointers ("content"), instead of the pointer's adresses. More...
class	ogdf::VComparer< E >
	Abstract base class for comparer classes. More...

Namespaces
namespace	ogdf
	The namespace for all OGDF objects.

Macros
#define	OGDF_AUGMENT_COMPARER(type)
	Add this macro to your class to turn it into a full comparer.
#define	OGDF_AUGMENT_STATICCOMPARER(type)
	Add this macro to your class to turn it into a full static comparer.
#define	OGDF_COMPARER_H
#define	OGDF_STD_COMPARER(type)
	Generates a specialization of the standard static comparer for type based on compare operators.

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Detailed Description

Declarations for Comparer objects.

Author:

Markus Chimani, Carsten Gutwenger

License:

This file is part of the Open Graph Drawing Framework (OGDF).

Copyright (C)
See README.txt in the root directory of the OGDF installation for details.

This program is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License Version 2 or 3 as published by the Free Software Foundation; see the file LICENSE.txt included in the packaging of this file for details.

This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details.

You should have received a copy of the GNU General Public License along with this program; if not, write to the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.

See also:

http://www.gnu.org/copyleft/gpl.html

Definition in file comparer.h.

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Macro Definition Documentation

#define OGDF_AUGMENT_COMPARER

(

type

)

Value:

public: \
    bool less(const type &x, const type &y) const { return compare(x,y) < 0; } \
    bool leq(const type &x, const type &y) const { return compare(x,y) <= 0; } \
    bool greater(const type &x, const type &y) const { return compare(x,y) > 0; } \
    bool geq(const type &x, const type &y) const { return compare(x,y) >= 0; } \
    bool equal(const type &x, const type &y) const { return compare(x,y) == 0; }

Add this macro to your class to turn it into a full comparer.

It is assumed that your class has a method "compare(const type &x, const type &y)", which returns 0 if the two elements are equal, a negative value if x is smaller, and a positive value if x is greater.

Note: If the compare function of your class requires no additional data other than the two elements to compare, your should usually use the more general OGDF_AUGMENT_STATICCOMPARER: A static comparer is also always valid as a normal comparer.

Usage in Definition:

 class MyComparer {
 private:
   Oracle oracle;
 public:
   MyComparer(Oracle o) : oracle(o) {}
   int compare(const MyStuff& x1, const MyStuff& x2) const {
      return ... //compare x1 with x2, using oracle
   }
   OGDF_AUGMENT_COMPARER(MyStuff)
 }

Use the Comparer:

 MyStuff a=...;
 MyStuff b=...;
 Oracle or;
 MyComparer comp(or);
 if( comp.less(a,b) )
   ... // do something
 ...
 Array<MyStuff> ay(10);
 ... // fill array
 ay.quicksort(comp); // sort the array using the MyComparer comp

Definition at line 171 of file comparer.h.

#define OGDF_AUGMENT_STATICCOMPARER

(

type

)

Value:

public: \
    static bool less(const type &x, const type &y) { return compare(x,y) < 0; } \
    static bool leq(const type &x, const type &y) { return compare(x,y) <= 0; } \
    static bool greater(const type &x, const type &y) { return compare(x,y) > 0; } \
    static bool geq(const type &x, const type &y) { return compare(x,y) >= 0; } \
    static bool equal(const type &x, const type &y) { return compare(x,y) == 0; }

Add this macro to your class to turn it into a full static comparer.

It is assumed that your class has a static method "compare(const type &x, const type &y)", which returns 0 if the two elements are equal, a negative value if x is smaller, and a positive value if x is greater.

Note: You should use this macro instead of OGDF_AUGMENT_COMPARER whenever your compare function requires no additional data stored in the object, other than the two elements to compare. A static comparer is also always valid as a normal comparer.

Usage in Definition:

 class MyComparer {
 public:
    static int comparer(const MyStuff& x1, const MyStuff& x2) {
       return ... //compare x1 with x2
    }
    OGDF_AUGMENT_STATICCOMPARER(MyStuff)
 }

Use the Comparer:

 MyStuff a=...;
 MyStuff b=...;
 MyComparer comp;
 if( MyComparer.less(a,b) ) // use it statically on the class
    ... // do something
 if( comp.less(a,b) ) // use it on the object
    ... // do something
 ...
 Array<MyStuff> ay(10);
 ... // fill array
 ay.quicksort(comp); // sort the array using the MyComparer comp

Definition at line 215 of file comparer.h.

#define OGDF_COMPARER_H

Definition at line 49 of file comparer.h.

#define OGDF_STD_COMPARER

(

type

)

Value:

template<> class StdComparer<type> \
    { \
    public: \
        static bool less   (const type &x, const type &y) { return x <  y; } \
        static bool leq    (const type &x, const type &y) { return x <= y; } \
        static bool greater(const type &x, const type &y) { return x >  y; } \
        static bool geq    (const type &x, const type &y) { return x >= y; } \
        static bool equal  (const type &x, const type &y) { return x == y; } \
    };

Generates a specialization of the standard static comparer for type based on compare operators.

Definition at line 91 of file comparer.h.