The BTK StrictlyChemicallyTyped Concept

Description:

A type that models StrictlyChemicallyTyped has an associated "chemical type" identifier (e.g. an atom or residue type), that is part of a self-consistent "chemical type system" (e.g. a set of atom and residue types that are specific to a particular type of molecule). The concept is "strict," because it does not allow the modification of either of these associated objects. This is essential when dealing with complex molecule types for which a change in chemical type following construction is difficult or undesirable.

Concept Refines:

STL Concepts:

None.

BTK Concepts:

None.

Notation:

X -- A type that models the StrictlyChemicallyTyped Concept
x -- An object of type X

Associated Types:

Chemical Type System Type	X::chemical_type_system	A type modelling the TypeSystem Concept
Dictionary Type	X::dictionary	A type modelling the Dictionary Concept
Chemical ID Type	X::id_type	A type modelling the TypeID Concept

Definitions:

None.

Valid Expressions:

In addition to those expressions specified by the refined concepts, the following expressions must be valid:

Expression	Type Requirements	Precondition	Semantics	Postcondition	Complexity
X::id_type x.type() const			Returns the chemical type ID of x.		O(1)
std::string x.name() const			If x.type() returns a defined chemical type, x.name() returns a non-empty string. Otherwise, x.name() returns an empty string.
X::chemical_type_system const & x.get_chemical_type_system() const			Returns a const reference to the chemical type system associated with x.		O(1)
X::dictionary const & x.get_dictionary() const			Returns a const reference to the dictionary_type associated with x.		O(1)

Models:

• BTK::ATOMS::Atom
• BTK::MOLECULES::AtomicStructure
• BTK::MOLECULES::Chain
• BTK::MOLECULES::Molecule
• BTK::MOLECULES::Monomer
• BTK::MOLECULES::PolymerStructure
• BTK::MOLECULES::Polymer

Invariants:

• X::dictionary is one of dictionary types defined in X::chemical_type_system.
• x.name() == (x.get_dictionary().find(x.type())).second
• x.type() == (x.get_dictionary().find(x.name())).first

Notes:

• For situations where a modifiable chemical type is desired, see the ChemicallyTyped Concept.

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