boost::value_visitor_invoker< T, FallbackPolicyT > Singleton Reference

Generic attribute value visitor invoker. More...

#include <value_visitation_fwd.hpp>

Inheritance diagram for boost::value_visitor_invoker< T, FallbackPolicyT >:

Collaboration diagram for boost::value_visitor_invoker< T, FallbackPolicyT >:

Public Types
typedef T	value_type
	Attribute value types. More...
typedef FallbackPolicyT	fallback_policy
	Fallback policy. More...
typedef visitation_result	result_type
	Function object result type. More...

Public Member Functions
	value_visitor_invoker (value_visitor_invoker const &that)
	Default constructor. More...
template<typename U >
	value_visitor_invoker (U const &arg)
	Initializing constructor. More...
template<typename VisitorT >
result_type	operator() (attribute_value const &attr, VisitorT visitor) const
	Visitation operator. More...
template<typename VisitorT >
result_type	operator() (attribute_name const &name, attribute_value_set const &attrs, VisitorT visitor) const
	Visitation operator. More...
template<typename VisitorT >
result_type	operator() (attribute_name const &name, record const &rec, VisitorT visitor) const
	Visitation operator. More...
template<typename VisitorT >
result_type	operator() (attribute_name const &name, record_view const &rec, VisitorT visitor) const
	Visitation operator. More...
fallback_policy const &	get_fallback_policy () const

Detailed Description

template<typename T, typename FallbackPolicyT>
singleton boost::value_visitor_invoker< T, FallbackPolicyT >

Generic attribute value visitor invoker.

Attribute value invoker is a functional object that attempts to find and extract the stored attribute value from the attribute value view or a log record. The extracted value is passed to a unary function object (the visitor) provided by user.

The invoker can be specialized on one or several attribute value types that should be specified in the second template argument.

Member Typedef Documentation

template<typename T, typename FallbackPolicyT>

typedef FallbackPolicyT boost::value_visitor_invoker< T, FallbackPolicyT >::fallback_policy

Fallback policy.

template<typename T, typename FallbackPolicyT>

typedef visitation_result boost::value_visitor_invoker< T, FallbackPolicyT >::result_type

Function object result type.

template<typename T, typename FallbackPolicyT>

typedef T boost::value_visitor_invoker< T, FallbackPolicyT >::value_type

Attribute value types.

Constructor & Destructor Documentation

template<typename T, typename FallbackPolicyT>

boost::value_visitor_invoker< T, FallbackPolicyT >::value_visitor_invoker ( value_visitor_invoker< T, FallbackPolicyT > const &  that )

inline

Default constructor.

Copy constructor

template<typename T, typename FallbackPolicyT>

template<typename U >

boost::value_visitor_invoker< T, FallbackPolicyT >::value_visitor_invoker ( U const &  arg )

inlineexplicit

Initializing constructor.

Parameters

arg	Fallback policy argument

Member Function Documentation

template<typename T, typename FallbackPolicyT>

fallback_policy const& boost::value_visitor_invoker< T, FallbackPolicyT >::get_fallback_policy ( ) const

inline

Returns

Fallback policy

Referenced by boost::expressions::format_date_time_terminal< T, FallbackPolicyT, CharT >::get_fallback_policy(), and boost::expressions::format_named_scope_terminal< FallbackPolicyT, CharT >::get_fallback_policy().

template<typename T, typename FallbackPolicyT>

template<typename VisitorT >

result_type boost::value_visitor_invoker< T, FallbackPolicyT >::operator() ( attribute_value const &  attr, VisitorT  visitor  ) const

inline

Visitation operator.

Attempts to acquire the stored value of one of the supported types. If acquisition succeeds, the value is passed to visitor.

Parameters

attr	An attribute value to apply the visitor to.
visitor	A receiving function object to pass the attribute value to.

Returns

The result of visitation.

Referenced by boost::value_visitor_invoker< channel_value_type, channel_fallback_policy >::operator()().

template<typename T, typename FallbackPolicyT>

template<typename VisitorT >

result_type boost::value_visitor_invoker< T, FallbackPolicyT >::operator() ( attribute_name const &  name, attribute_value_set const &  attrs, VisitorT  visitor  ) const

inline

Visitation operator.

Looks for an attribute value with the specified name and tries to acquire the stored value of one of the supported types. If acquisition succeeds, the value is passed to visitor.

Parameters

name	Attribute value name.
attrs	A set of attribute values in which to look for the specified attribute value.
visitor	A receiving function object to pass the attribute value to.

Returns

The result of visitation.

template<typename T, typename FallbackPolicyT>

template<typename VisitorT >

result_type boost::value_visitor_invoker< T, FallbackPolicyT >::operator() ( attribute_name const &  name, record const &  rec, VisitorT  visitor  ) const

inline

Visitation operator.

Looks for an attribute value with the specified name and tries to acquire the stored value of one of the supported types. If acquisition succeeds, the value is passed to visitor.

Parameters

name	Attribute value name.
rec	A log record. The attribute value will be sought among those associated with the record.
visitor	A receiving function object to pass the attribute value to.

Returns

The result of visitation.

template<typename T, typename FallbackPolicyT>

template<typename VisitorT >

result_type boost::value_visitor_invoker< T, FallbackPolicyT >::operator() ( attribute_name const &  name, record_view const &  rec, VisitorT  visitor  ) const

inline

Visitation operator.

Looks for an attribute value with the specified name and tries to acquire the stored value of one of the supported types. If acquisition succeeds, the value is passed to visitor.

Parameters

name	Attribute value name.
rec	A log record view. The attribute value will be sought among those associated with the record.
visitor	A receiving function object to pass the attribute value to.

Returns

The result of visitation.

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

• boost_1_57_0/boost/log/attributes/value_visitation.hpp