#include <CGAL/utility.h>












 first element 

 second element 

 third element 

 fourth element 
 
introduces a quadruple using the
default constructor of the four elements.
 
 
constructs a
quadruple such that first is constructed from x,
second is constructed from y, third is
constructed from z, and fourth is constructed from
w.
 
 
 
constructs a quadruple such that
first is constructed from u, second is
constructed from v, third is constructed from w,
and fourth is constructed from x. Requirement: Proper conversion operators exist from U to T1, V to T2, W to T3, and X to T4.

 

 The comparison operator. It uses lexicographic comparison: the return value is true if the first element of x is less than the first element of y, and false if the first element of y is less than the first element of x. If neither of these is the case, then it returns true if the second element of x is less than the second element of y, and false if the second element of y is less than the second element of x. If neither of these is the case, then it returns true if the third element of x is less than the third element of y, and false if the third element of y is less than the third element of x. If neither of these is the case, then it returns the result of comparing the fourth elements of x and y. This operator may only be used if T1, T2, T3, and T4 define the comparison operator. 
 

 The equality operator. The return value is true if and only the first elements of x and y are equal, the second elements of x and y are equal, the third elements of x and y are equal, and the fourth elements of x and y are equal. This operator may only be used if T1, T2, T3, and T4 define the equality operator. 
 
 
 
Equivalent to Quadruple<T1, T2, T3, T4>(x, y, z, w). 