rttr::constructor Class Reference

The constructor class provides several meta information about a constructor and can be invoked. More...

#include <constructor.h>

Public Member Functions
type	get_declaring_type () const
	Returns the type of the class or struct that declares this constructor. More...
type	get_instanciated_type () const
	Returns the type object of the instantiated type. More...
variant	get_metadata (int key) const
	Returns the metadata for the given key key. More...
variant	get_metadata (const std::string &key) const
	Returns the metadata for the given key key. More...
std::vector< type >	get_parameter_types () const
	Returns a list of type objects representing the number, order and type of the parameters for this constructor. More...
std::string	get_signature () const
	Returns the signature of this constructor as readable string. More...
variant	invoke () const
	Invokes the constructor of type returned by get_instanciated_type(). More...
variant	invoke (detail::argument arg1) const
	Invokes the constructor of type returned by get_instanciated_type(). More...
variant	invoke (detail::argument arg1, detail::argument arg2) const
	Invokes the constructor of type returned by get_instanciated_type(). More...
variant	invoke (detail::argument arg1, detail::argument arg2, detail::argument arg3) const
	Invokes the constructor of type returned by get_instanciated_type(). More...
variant	invoke (detail::argument arg1, detail::argument arg2, detail::argument arg3, detail::argument arg4) const
	Invokes the constructor of type returned by get_instanciated_type(). More...
variant	invoke (detail::argument arg1, detail::argument arg2, detail::argument arg3, detail::argument arg4, detail::argument arg5) const
	Invokes the constructor of type returned by get_instanciated_type(). More...
variant	invoke (detail::argument arg1, detail::argument arg2, detail::argument arg3, detail::argument arg4, detail::argument arg5, detail::argument arg6) const
	Invokes the constructor of type returned by get_instanciated_type(). More...
variant	invoke_variadic (std::vector< detail::argument > args) const
	Invokes the constructor of type returned by get_instanciated_type(). More...
bool	is_valid () const
	Returns true if this constructor is valid, otherwise false. More...
	operator bool () const
	Convenience function to check if this constructor is valid or not. More...
bool	operator!= (const constructor &other) const
	Returns true if this constructor is the not the same like the other. More...
bool	operator== (const constructor &other) const
	Returns true if this constructor is the same like the other. More...

Detailed Description

The constructor class provides several meta information about a constructor and can be invoked.

A instance of a constructor class can only be obtained from the type class. See type::get_constructor() and type::get_constructors().

For registration a constructor, nested inside a class, see class_::constructor() and for global constructors see constructor_.

Meta Information

A constructor has a signature (get_signature()) and a instantiate exactly one type (get_instanciated_type()). With get_parameter_types() you retrieve all type objects of the parameters for this constructor. When the constructor was declared inside a class, then get_declaring_type() can be used to obtain the type of this class.

The method can be invoked with invoke(); When its not a static method you have to provide a class instance to invoke the method. This instance can be the raw type on the stack; the current hierarchy level doesn't matter. It can be also a raw pointer to the object or a variant which contains the instance, again as pointer or stack object.

Another way to invoke a method is to use the type class through type::create().

Copying and Assignment

A constructor object is lightweight and can be copied by value. However, each copy will refer to the same underlying constructor.

Typical Usage

constructor string_ctor == type::get("std::string").get_constructor({type::get("const char*")});

variant my_string = string_ctor.invoke({"Hello World"}); // returns an ptr to the object on the heap

std::cout << my_string.get_value<std::string*>()->c_str() << std::endl; // prints 'Hello World'

// don't forget to destroy the instance
type::get("std::string").get_destructor().invoke(my_string);

my_string.is_valid(); // yield to false

See also

method, property, enumeration, destructor and type

Member Function Documentation

type rttr::constructor::get_declaring_type

(

)

const

Returns the type of the class or struct that declares this constructor.

Remarks

When this constructor does not belong to a class (i.e. is a primitive type) it will return an invalid type object. When this constructor is not valid, this function will return an invalid type object (see type::is_valid).

Returns

Type of the declaring class/struct for this enumeration.

type rttr::constructor::get_instanciated_type

(

)

const

Returns the type object of the instantiated type.

Returns

The instantiated type.

variant rttr::constructor::get_metadata

(

int

key

)

const

Returns the metadata for the given key key.

Remarks

When no metadata is registered with the given key, an invalid variant object is returned (see variant::is_valid).

Returns

A variant object, containing arbitrary data.

variant rttr::constructor::get_metadata

(

const std::string &

key

)

const

Returns the metadata for the given key key.

Remarks

When no metadata is registered with the given key, an invalid variant object is returned (see variant::is_valid).

Returns

A variant object, containing arbitrary data.

std::vector<type> rttr::constructor::get_parameter_types

(

)

const

Returns a list of type objects representing the number, order and type of the parameters for this constructor.

Returns

A list representing the parameters of this constructor.

std::string rttr::constructor::get_signature

(

)

const

Returns the signature of this constructor as readable string.

Returns

The signature as readable string.

variant rttr::constructor::invoke

(

)

const

Invokes the constructor of type returned by get_instanciated_type().

The instance will always be created on the heap and will be returned as variant object.

Remarks

Returns an invalid variant object (see variant::is_valid), when the arguments does not match the parameters of the underlying constructor.

Returns

An instance of the type get_instanciated_type().

variant rttr::constructor::invoke

(

detail::argument

arg1

)

const

Invokes the constructor of type returned by get_instanciated_type().

The instance will always be created on the heap and will be returned as variant object.

Remarks

Returns an invalid variant object (see variant::is_valid), when the arguments does not match the parameters of the underlying constructor.

Returns

An instance of the type get_instanciated_type().

variant rttr::constructor::invoke	(	detail::argument	arg1,
		detail::argument	arg2
	)		const

Invokes the constructor of type returned by get_instanciated_type().

The instance will always be created on the heap and will be returned as variant object.

Remarks

Returns an invalid variant object (see variant::is_valid), when the arguments does not match the parameters of the underlying constructor.

Returns

An instance of the type get_instanciated_type().

variant rttr::constructor::invoke	(	detail::argument	arg1,
		detail::argument	arg2,
		detail::argument	arg3
	)		const

Invokes the constructor of type returned by get_instanciated_type().

The instance will always be created on the heap and will be returned as variant object.

Remarks

Returns an invalid variant object (see variant::is_valid), when the arguments does not match the parameters of the underlying constructor.

Returns

An instance of the type get_instanciated_type().

variant rttr::constructor::invoke	(	detail::argument	arg1,
		detail::argument	arg2,
		detail::argument	arg3,
		detail::argument	arg4
	)		const

Invokes the constructor of type returned by get_instanciated_type().

The instance will always be created on the heap and will be returned as variant object.

Remarks

Returns an invalid variant object (see variant::is_valid), when the arguments does not match the parameters of the underlying constructor.

Returns

An instance of the type get_instanciated_type().

variant rttr::constructor::invoke	(	detail::argument	arg1,
		detail::argument	arg2,
		detail::argument	arg3,
		detail::argument	arg4,
		detail::argument	arg5
	)		const

Invokes the constructor of type returned by get_instanciated_type().

The instance will always be created on the heap and will be returned as variant object.

Remarks

Returns an invalid variant object (see variant::is_valid), when the arguments does not match the parameters of the underlying constructor.

Returns

An instance of the type get_instanciated_type().

variant rttr::constructor::invoke	(	detail::argument	arg1,
		detail::argument	arg2,
		detail::argument	arg3,
		detail::argument	arg4,
		detail::argument	arg5,
		detail::argument	arg6
	)		const

Invokes the constructor of type returned by get_instanciated_type().

The instance will always be created on the heap and will be returned as variant object.

Remarks

Returns an invalid variant object (see variant::is_valid), when the arguments does not match the parameters of the underlying constructor.

Returns

An instance of the type get_instanciated_type().

variant rttr::constructor::invoke_variadic

(

std::vector< detail::argument >

args

)

const

Invokes the constructor of type returned by get_instanciated_type().

The instance will always be created on the heap and will be returned as variant object. Use this method when you need to instantiate a constructor with more then 6 parameters.

Remarks

Using this invoke function is slower, then specifying the arguments directly. Returns an invalid variant object (see variant::is_valid), when the arguments does not match the parameters of the underlying constructor.

Returns

An instance of the type get_instanciated_type().

bool rttr::constructor::is_valid

(

)

const

Returns true if this constructor is valid, otherwise false.

Returns

True if this constructor is valid, otherwise false.

rttr::constructor::operator bool

(

)

const

Convenience function to check if this constructor is valid or not.

Returns

True if this constructor is valid, otherwise false.

bool rttr::constructor::operator!=

(

const constructor &

other

)

const

Returns true if this constructor is the not the same like the other.

Returns

True if both constructors are different, otherwise false.

bool rttr::constructor::operator==

(

const constructor &

other

)

const

Returns true if this constructor is the same like the other.

Returns

True if both constructors are equal, otherwise false.

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

• constructor.h