function_types.qbk

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Determines whether a given type is a pointer to member object type. 

[endsect]


[section:is_member_function_pointer is_member_function_pointer]

  template<typename T, typename Tag = __null_tag>
  struct is_member_function_pointer;

[*Header]

  #include <boost/function_types/is_member_function_pointer.hpp>

[variablelist
  [[[^T]][Type to analyze]]
  [[[^Tag]][Further properties required for a positive result]]
  [[[^is_member_function_pointer<T,Tag>]][Predicate value __mpl_integral_constant__]]
  [[[^is_member_function_pointer<T,Tag>::value]][Constant boolean value]]
]

Determines whether a given type is a member function pointer, possibly with
additional properties as specified by a property tag.

[endsect]


[section:is_callable_builtin is_callable_builtin]

  template<typename T, typename Tag = __null_tag>
  struct is_callable_builtin;

[*Header]

  #include <boost/function_types/is_callable_builtin.hpp>

[variablelist
  [[[^T]][Type to analyze]]
  [[[^Tag]][Further properties required for a positive result]]
  [[[^is_callable_builtin<T,Tag>]][Predicate value as __mpl_integral_constant__]]
  [[[^is_callable_builtin<T,Tag>::value]][Constant boolean value]]
]

Determines whether a given type is a callable builtin, possibly with
additional properties as specified by a property tag.

[endsect]



[section:is_nonmember_callable_builtin is_nonmember_callable_builtin]

  template<typename T, typename Tag = __null_tag>
  struct is_nonmember_callable_builtin;

[*Header]

  #include <boost/function_types/is_nonmember_callable_builtin.hpp>

[variablelist
  [[[^T]][Type to analyze]]
  [[[^Tag]][Further properties required for a positive result]]
  [[[^is_nonmember_callable_builtin<T,Tag>]][Predicate value as __mpl_integral_constant__]]
  [[[^is_nonmember_callable_builtin<T,Tag>::value]][Constant boolean value]]
]

Determines whether a given type is a callable builtin that is not a
member function pointer, possibly with
additional properties as specified by a property tag.

[endsect]


[endsect] [/ Class templates for type classification ]

[/ ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ ]

[section:decomposition Class templates for type decomposition]


[section:result_type result_type]

  template<typename F>
  struct result_type;

[*Header]

  #include <boost/function_types/result_type.hpp>

[variablelist
  [[[^F]][Type to analyze]]
  [[[^result_type<F>::type]][Result type of [^F]]]
]

Extracts the result type of a callable, builtin type.

If [^F] is no callable, builtin type, any attempt to access the
[^type] member results in a compile error.

[endsect]


[section:parameter_types parameter_types]

  template<typename F, class ClassTransform = add_reference<_> >
  struct parameter_types;

[*Header]

  #include <boost/function_types/parameter_types.hpp>

[variablelist
  [[[^F]][Type to analyze]]
  [[[^ClassTransform]]
   [__mpl_lambda_expression__ to transform the 
    class type if [^F] is a member function pointer]]

  [[[^parameter_types<F,ClassTransform>]]
   [__mpl_fb_ext_ra_seq__ of parameter types]]
]

Extracts the parameter types of a callable, builtin type.

If [^F] is no callable, builtin type, any attempt to access the
sequence results in a compile error.

[endsect]


[section:function_arity function_arity]

  template<typename F>
  struct function_arity;

[*Header]

  #include <boost/function_types/function_arity.hpp>

[variablelist
  [[[^F]][Callable builtin type]]
  [[[^function_arity<F>]][Function arity as __mpl_integral_constant__]]
  [[[^function_arity<F>::value]][Constant value of the function arity]]
]

Extracts the function arity, that is the number of parameters. 
The hidden [^this] of member function pointers counts, in other words
the arity value is always greater than or equal to one if [^F] is a 
member function pointer.

If [^F] is no callable, builtin type, any attempt to access the
value results in a compile error.

[endsect]


[section:components components]

  template<typename T, class ClassTransform = add_reference<_> >
  struct components;

[*Header]

  #include <boost/function_types/components.hpp>

[variablelist
  [[[^T]][Type to analyze]]
  [[[^ClassTransform]]
   [__mpl_lambda_expression__ to transform the 
    class type if [^T] is a member function pointer]]

  [[[^components<T,ClassTransform>]]
   [__mpl_fb_ext_ra_seq__ of all 
     component types and property tag]]
  [[[^components<T,ClassTransform>::types]]
   [Decorated MPL Sequence, exposed for optimization]]
]

Extracts all properties of a callable builtin type, that is the result type,
followed by the parameter types (including the type of [^this] for member 
function pointers).

If [^T] is no callable builtin type, the component types are an empty
sequence and the Tag's meaning is equivalent to the [^__null_tag].

[endsect]

[endsect] [/ Class templates for type decomposition]

[/ ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ ]

[section:synthesis Class templates for type synthesis]


[section:function_type function_type]

  template<typename Types, typename Tag = __null_tag> 
  struct function_type;

[*Header]

  #include <boost/function_types/function_type.hpp>

[variablelist
  [[[^Types]][Component types in form of an __mpl_fwd_seq__ or another callable, builtin type]]
  [[[^Tag]][Further properties]]
  [[[^function_type<Types,Tag>::type]][Synthesized type]]
]

Synthesizes a function type from given properties.

If the template parameters do not describe a valid type, any attempt
to access the [^type] member will result in a compile error.

[endsect]


[section:function_pointer function_pointer]

  template<typename Types, typename Tag = __null_tag> 
  struct function_pointer;

[*Header]

  #include <boost/function_types/function_pointer.hpp>

[variablelist
  [[[^Types]][Component types in form of an __mpl_fwd_seq__ or another callable, builtin type]]
  [[[^Tag]][Further properties]]
  [[[^function_pointer<Types,Tag>::type]][Synthesized type]]
]

Synthesizes a function pointer type from given properties.

If the template parameters do not describe a valid type, any attempt
to access the [^type] member will result in a compile error.

[endsect]


[section:function_reference function_reference]

  template<typename Types, typename Tag = __null_tag> 
  struct function_reference;

[*Header]

  #include <boost/function_types/function_reference.hpp>

[variablelist
  [[[^Types]][Component types in form of an __mpl_fwd_seq__ or another callable, builtin type]]
  [[[^Tag]][Further properties]]
  [[[^function_reference<Types,Tag>::type]][Synthesized type]]
]

Synthesizes a function reference type from given properties.

If the template parameters do not describe a valid type, any attempt
to access the [^type] member will result in a compile error.

[endsect]


[section:member_function_pointer member_function_pointer]

  template<typename Types, typename Tag = __null_tag> 
  struct member_function_pointer;

[*Header]

  #include <boost/function_types/member_function_pointer.hpp>

[variablelist
  [[[^Types]][Component types in form of an __mpl_fwd_seq__ or another callable, builtin type]]
  [[[^Tag]][Further properties]]
  [[[^member_function_pointer<Types,Tag>::type]][Synthesized type]]
]

Synthesizes a member function pointer type from given properties.

An optional reference or possibly cv-qualified pointer is removed from
the second type in the sequence to determine the the class type. 
The cv-qualification of the resulting type applies to the member
function, unless otherwise explicitly specified by the property tag.

If the template parameters do not describe a valid type, any attempt
to access the [^type] member will result in a compile error.

[endsect]


[endsect] [/ Class templates for type synthesis ]

[/ ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ ]

[section:tag_types Tag Types]

[section:variadic variadic]

  typedef __unspecified__ variadic;

[*Header]

  #include <boost/function_types/property_tags.hpp>

States that a function type takes a variable number of arguments through 
an ellipsis parameter (such as [^printf]).

[endsect]

[section:non_variadic non_variadic]

  typedef __unspecified__ non_variadic;

[*Header]

  #include <boost/function_types/property_tags.hpp>

States that a function type does not have an ellipsis parameter.

[endsect]

[section:default_cc default_cc]

  typedef __unspecified__ default_cc;

[*Header]

  #include <boost/function_types/property_tags.hpp>

States that a function type encodes the default calling convention.

[endsect]

[section:const_qualified const_qualified]

  typedef __unspecified__ const_qualified;

[*Header]

  #include <boost/function_types/property_tags.hpp>

States that a function type is const qualified.

[endsect]

[section:non_const non_const]

  typedef __unspecified__ non_const;

[*Header]

  #include <boost/function_types/property_tags.hpp>

States that a function type is not const qualified.

[endsect]

[section:volatile_qualified volatile_qualified]

  typedef __unspecified__ volatile_qualified;

[*Header]

  #include <boost/function_types/property_tags.hpp>

States that a function type is volatile qualified.

[endsect]