 

Category: functors   Component type: concept 
Description
An Adaptable Unary Function is a UnaryFunction with nested typedef
s that define its argument type and result type. [1] [2] These nested typedef
make it possible to use function object adaptors.
Refinement of
UnaryFunction
Associated types
Argument type  F::argument_type  The type of F 's argument 
Result type  F::result_type  The type returned when the Unary Function is called 
Notation
F  A type that is a model of Unary Function 
Definitions
Valid expressions
None, except for those defined by UnaryFunction
Expression semantics
Complexity guarantees
Invariants
Models
Notes
[1] Note the implication of this: a function pointer T (*f)(X)
is a UnaryFunction, but not an Adaptable Unary Function: the expressions f::argument_type
and f::result_type
are nonsensical.
[2] When you define a class that is a model of Adaptable Unary Function, you must provide these typedef
s. The easiest way to do this is to derive the class from the base class unary_function
. This is an empty class, with no member functions or member variables; the only reason it exists is to make defining Adaptable Unary Functions more convenient. unary_function
is very similar to the base classes used by the iterator_tags functions.
See also
UnaryFunction, AdaptableGenerator, AdaptableBinaryFunction