Cmp Class Template Reference

#include <Cmp.hh>

List of all members.

Detailed Description

template<typename T>
class Rivet::Cmp< T >

Cmp is a helper class to be used when checking the ordering of two objects. When implicitly converted to an integer the value will be negative if the two objects used in the constructor are ordered and positive if they are not. Zero will be returned if they are equal.

The main usage of the Cmp class is if several variables should be checked for ordering in which case several Cmp objects can be combined as follows: cmp(a1, a2) || cmp(b1, b2) || cmp(c1, c2) where cmp is a global function for easy creation of Cmp objects.

Definition at line 25 of file Cmp.hh.


Public Member Functions

 operator CmpState () const
 Automatically convert to an enum.
 operator int () const
 Automatically convert to an integer.
template<typename U>
const Cmp< T > & operator|| (const Cmp< U > &c) const
 If this state is equivalent, set this state to the state of c.
Standard constructors etc.
 Cmp (const T &t1, const T &t2)
 The default constructor.
template<typename U>
 Cmp (const Cmp< U > &x)
 The copy constructor.
 ~Cmp ()
 The destructor is not virtual since this is not intended to be a base class.
template<typename U>
const Cmp< T > & operator= (const Cmp< U > &x)
 The assignment operator.

Private Member Functions

void _compare () const
 Perform the actual comparison if necessary.

Private Attributes

CmpState _value
 The state of this object.
pair< const T *, const T * > _objects
 The objects to be compared.

Constructor & Destructor Documentation

Cmp ( const T &  t1,
const T &  t2 
) [inline]

The default constructor.

Definition at line 31 of file Cmp.hh.

00032       : _value(UNDEFINED), _objects(&t1, &t2) { }

Cmp ( const Cmp< U > &  x  )  [inline]

The copy constructor.

Definition at line 36 of file Cmp.hh.

00037       : _value(x), _objects(0, 0) { }

~Cmp (  )  [inline]

The destructor is not virtual since this is not intended to be a base class.

Definition at line 40 of file Cmp.hh.

00040 { };

Member Function Documentation

const Cmp<T>& operator= ( const Cmp< U > &  x  )  [inline]

The assignment operator.

Definition at line 44 of file Cmp.hh.

References Cmp::_value.

00044                                              {
00045       _value = x;
00046       return *this;
00047     }

operator CmpState (  )  const [inline]

Automatically convert to an enum.

Definition at line 53 of file Cmp.hh.

References Cmp::_compare(), and Cmp::_value.

00053                               {
00054       _compare();
00055       return _value;
00056     }

operator int (  )  const [inline]

Automatically convert to an integer.

Definition at line 59 of file Cmp.hh.

References Cmp::_compare(), and Cmp::_value.

00059                          {
00060       _compare();
00061       return _value;
00062     }

const Cmp<T>& operator|| ( const Cmp< U > &  c  )  const [inline]

If this state is equivalent, set this state to the state of c.

Definition at line 66 of file Cmp.hh.

References Cmp::_compare(), Cmp::_value, and Rivet::EQUIVALENT.

00066                                                     {
00067       _compare();
00068       if (_value == EQUIVALENT) _value = c;
00069       return *this;
00070     }

void _compare (  )  const [inline, private]

Perform the actual comparison if necessary.

Definition at line 75 of file Cmp.hh.

References Cmp::_objects, Cmp::_value, Rivet::EQUIVALENT, Rivet::ORDERED, Rivet::UNDEFINED, and Rivet::UNORDERED.

Referenced by Cmp< double >::operator CmpState(), Cmp< Projection >::operator CmpState(), Cmp::operator CmpState(), Cmp< double >::operator int(), Cmp< Projection >::operator int(), Cmp::operator int(), Cmp< double >::operator||(), Cmp< Projection >::operator||(), and Cmp::operator||().

00075                           {
00076       if (_value == UNDEFINED) {
00077         less<T> l;
00078         if ( l(*_objects.first, *_objects.second) ) _value = ORDERED;
00079         else if ( l(*_objects.second, *_objects.first) ) _value = UNORDERED;
00080         else _value = EQUIVALENT;
00081       }
00082     }

Member Data Documentation

CmpState _value [mutable, private]

The state of this object.

Definition at line 85 of file Cmp.hh.

Referenced by Cmp< double >::_compare(), Cmp< Projection >::_compare(), Cmp::_compare(), Cmp< double >::operator CmpState(), Cmp< Projection >::operator CmpState(), Cmp::operator CmpState(), Cmp< double >::operator int(), Cmp< Projection >::operator int(), Cmp::operator int(), Cmp< double >::operator=(), Cmp< Projection >::operator=(), Cmp::operator=(), Cmp< double >::operator||(), Cmp< Projection >::operator||(), and Cmp::operator||().

pair<const T*, const T*> _objects [private]

The objects to be compared.

Definition at line 88 of file Cmp.hh.

Referenced by Cmp< Projection >::_compare(), and Cmp::_compare().

The documentation for this class was generated from the following file: