command-signature.hpp File Reference

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Description

Metaprogramming helpers for deriving the precise function signatures necessary to implement a given command.

Basically, commands can be implemented by arbitrary functions, but the signatures of the operation function, the undo function and the undo state capturing function are required to obey fixed relationships. Thus, at various stages of the command definition, we need to accept functor objects with a very specific and predetermined signature, thus allowing for strict type checking by the compiler.

Relation of function signatures (MEM = type of the "memento" for Undo)

• operation: void(P1,..PN)
• captureUndo: MEM(P1,..PN)
• undoOperation void(P1,..PN,MEM)
• bind takes the arguments:(P1,..PN)

See also

Command

CommandDef

Definition in file command-signature.hpp.

#include "lib/meta/function.hpp"
#include "lib/meta/typelist.hpp"
#include "lib/meta/typelist-manip.hpp"
#include "lib/meta/typeseq-util.hpp"
#include <functional>

Classes
struct	UndoSignature< SIG >::Case< RET, ARG >
	Case1: defining the Undo-Capture function. More...
struct	UndoSignature< SIG >::Case< void, ARG >
	Case2: defining the actual Undo function. More...
class	CommandSignature< SIG, MEM >
	Metaprogramming helper for building Command function signatures. More...
class	UndoSignature< SIG >
	Type analysis helper template. More...

Functions
	LUMIERA_ERROR_DECLARE (UNBOUND_ARGUMENTS)
	Command functor not yet usable, because arguments aren't bound.
	LUMIERA_ERROR_DECLARE (MISSING_MEMENTO)
	Undo functor not yet usable, because no undo state has been captured.

Namespaces
	lumiera
	Lumiera public interface.
	steam
	Steam-Layer implementation namespace root.
	steam::control
	Steam-Layer dispatcher, controller and administrative facilities.

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Class Documentation

steam::control::UndoSignature::Case

struct steam::control::UndoSignature::Case

Class Members
typedef RET	Memento
typedef typename Append< ARG, Memento >::List	ExtendedArglist
typedef typename Types < ExtendedArglist >::Seq	ExtendedArgs
typedef typename BuildFunType < void, ARG >::Sig	OperateSig
typedef typename BuildFunType < Ret, ARG >::Sig	CaptureSig
typedef typename BuildFunType < void, ExtendedArgs >::Sig	UndoOp_Sig

Collaboration diagram for UndoSignature< SIG >::Case< RET, ARG >:

steam::control::UndoSignature::Case< void, ARG >

struct steam::control::UndoSignature::Case< void, ARG >

Class Members
typedef typename List	Args
typedef typename SplitLast < Args >::Type	Memento
typedef typename SplitLast < Args >::List	OperationArglist
typedef typename Types < OperationArglist >::Seq	OperationArgs
typedef typename BuildFunType < void, OperationArgs >::Sig	OperateSig
typedef typename BuildFunType < Ret, OperationArgs >::Sig	CaptureSig
typedef typename BuildFunType < void, ARG >::Sig	UndoOp_Sig

Collaboration diagram for UndoSignature< SIG >::Case< void, ARG >: