Description

Provision for setup of concrete commands for use by the UI.

A Steam-Layer command is a functor, which can be parametrised with actual arguments. It needs to be defined beforehand, which means to establish an unique name and to supply three functions, one for the actual command operation, one to capture state and one to undo the effect of the command invocation. CommandSetup allows to create series of such definitions with minimal effort. Since any access and mutation from the UI into the Session data must be performed by invoking such commands, a huge amount of individual command definitions need to be written eventually.

The macro COMMAND_DEFINITION(NAME) allows to introduce a new definition with a single line, followed by a code block, which actually ends up as the body of a lambda function, and receives the bare CommandDef as single argument with name cmd. The _NAME_ argument of the macro ends up both stringified as the value of the command-ID, and as an variable holding a new CommandSetup instance. It is assumed that a header with corresponding declarations (the header cmd.hpp) is included by all UI elements actually to use, handle and invoke commands towards the session-command-facade.h

See also: command-def.hpp; command.hpp; CommandSetup_test; cmd.hpp; cmd-context.hpp

Definition in file command-setup.hpp.

#include "lib/error.hpp"
#include "lib/nocopy.hpp"
#include "steam/control/command.hpp"
#include "lib/symbol.hpp"
#include <functional>
#include <string>

Classes
class	CommandSetup
	Marker and Helper for writing Steam-Layer Command definitions. More...

Typedefs
using	DefinitionClosure = std::function< void(CommandDef &)>

Macros
#define	COMMAND_DEFINITION(_NAME_) CommandSetup _NAME_ = CommandSetup{STRINGIFY(_NAME_)} = [&](CommandDef& def)
	Macro to write command definitions in a compact form. More...

Namespaces
	steam
	Steam-Layer implementation namespace root.

	steam::control
	Steam-Layer dispatcher, controller and administrative facilities.

Macro Definition Documentation

◆ COMMAND_DEFINITION

#define COMMAND_DEFINITION ( _NAME_ ) CommandSetup _NAME_ = CommandSetup{STRINGIFY(_NAME_)} = [&](CommandDef& def)

Macro to write command definitions in a compact form.

On expansion, a variable of type CommandSetup will be defined in the current scope, and immediately be assigned by a lambda, whose body is what follows the macro invocation

Definition at line 144 of file command-setup.hpp.

Description

Classes

Typedefs

Macros

Namespaces

Macro Definition Documentation

◆ COMMAND_DEFINITION