Element Class Template Reference
[Fundamental C++: the Element design pattern.]

Glue class between structural elements and implementation values. More...

Inheritance diagram for Element:

[legend]List of all members.

Public Types
typedef S	set_t
	Structure type for structural elements.
typedef T	value_t
	Implementation type for values.
Public Member Functions
	Element ()
	Default constructor.
	Element (const Element &other)
	Copy constructor from Element instances of exactly the same type.
template<typename U>
	Element (const Element< S, U > &other)
	Copy constructor from Element instances with different value type.
template<typename OtherS, typename U>
	Element (const Element< OtherS, U > &other)
	Copy constructor from foreign Element instances.
	Element (const S &structure)
	Default constructor with the structural element specified.
	Element (const S &structure, const T &other)
	Explicit construction from structural element and value.
template<typename U>
	Element (const S &structure, const U &other)
	Explicit construction from structural element and foreign value.
template<typename OtherS, typename U>
	Element (const S &structure, const Element< OtherS, U > &other)
	Explicit construction with foreign Element conversion.
Element &	operator= (const Element &other)
	Assignment from the same Element type.
template<typename U>
Element &	operator= (const Element< S, U > &other)
	Assignment from other implementation value types.
template<typename OtherS, typename U>
Element &	operator= (const Element< OtherS, U > &other)
	Assignment from foreign Element types.
template<typename U>
Element &	operator= (const U &other)
	Assignment from foreign implementation types.
const S &	structure () const
	Accessor to the structural element.
void	attach (const S &structure)
	Post-construction link to a structural element.
	Element (const T &other)
	Copy constructor from anonymous values.
template<typename U>
	Element (const U &other)
	Copy constructor from anonymous values.
T &	value ()
	Accessor to the value data.
const T &	value () const
	Accessor to the value data.
Static Public Attributes
static const bool	dynamic
	Attribute indicating whether Element instances have run-time data.

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Detailed Description

template<typename S, typename T>
class vcsn::Element< S, T >

Glue class between structural elements and implementation values.

Element is the center of the design pattern used in Vaucanson to have an orthogonal construction of object from two different viewpoints:

• Algebraic/Theorical one, from a hierarchy of structures,
• Implementation and computations.

Element proposes a lot of different constructors so as to allow the largest structure of type conversions. Calling foreign constructors assumes that there exist compatible op_convert() functions.

See also:

• MetaElement
• Structure
• SetSlot

Definition at line 61 of file element.hh.

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Constructor & Destructor Documentation

Element (   )

Default constructor. It is not possible to use this contructor when the structural element has dynamic data. If you absolutely need to do so, notice that it may be dangerous, and see utility::Deferrer. See also: utility::Deferrer Definition at line 30 of file element.hxx. References static_assertion_.

Element (  const Element< OtherS, U > &  other  )

Copy constructor from foreign Element instances. Impossible to use when the structural element has dynamic data since it leaves it uninitialized. Definition at line 59 of file element.hxx.

Element (  const T &  other  )

Copy constructor from anonymous values. Impossible to use when the structural element has dynamic data since it leaves it uninitialized. Definition at line 71 of file element.hxx. References static_assertion_.

Element (  const U &  other  )

Copy constructor from anonymous values. Impossible to use when the structural element has dynamic data since it leaves it uninitialized. Definition at line 81 of file element.hxx. References static_assertion_.

Element (  const S &  structure  )  [explicit]

Default constructor with the structural element specified. Invokes the default constructor of the implementation value type. Definition at line 94 of file element.hxx.

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