set is an Associative Sequence of heterogeneous typed data elements. Type identity is used to impose an equivalence relation on keys. The element's type is its key. A set may contain at most one element for each key. Membership testing and element key lookup has constant runtime complexity (see Overloaded Functions).
#include <boost/fusion/container/set.hpp> #include <boost/fusion/include/set.hpp> #include <boost/fusion/container/set/set_fwd.hpp> #include <boost/fusion/include/set_fwd.hpp>
template < typename T0 = unspecified , typename T1 = unspecified , typename T2 = unspecified ... , typename TN = unspecified > struct set;
For C++11 compilers, the variadic function interface has no upper bound.
For C++03 compilers, the variadic class interface accepts 0
to FUSION_MAX_SET_SIZE
elements,
where FUSION_MAX_SET_SIZE
is a user definable predefined maximum that defaults to 10
.
Example:
set<int, char, double>
You may define the preprocessor constant FUSION_MAX_SET_SIZE
before including any Fusion header to change the default. Example:
#define FUSION_MAX_SET_SIZE 20
Parameter 
Description 
Default 


Element types 
unspecified 
Notation
S
A set
type
s
An instance of set
e0
...en
Heterogeneous values
fs
Semantics of an expression is defined only where it differs from, or is not defined in Random Access Sequence and Associative Sequence.
Expression 
Semantics 


Creates a set with default constructed elements. 

Creates a set with elements 

Copy constructs a set from a Forward
Sequence 

Assigns to a set, 
typedef set<int, float> S; S s(12, 5.5f); std::cout <<at_key
<int>(s) << std::endl; std::cout <<at_key
<float>(s) << std::endl; std::cout <<result_of::has_key
<S, double>::value << std::endl;