Xtext @ Profict Summer Camp

Kiel, Germany

Jan Peter Dennis

“... won’t talk about model-driven stuff”

You’re lucky!

No UML!

No MDA! No meta meta meta meta ...

Hands-on a concrete example taken from Martin Fowler’s upcoming Book on DSLs

You’re working for a company specialized on systems for secret compartments

Your customer: Mrs. H she likes secrets

To open the secret compartment, she has to

To open the secret compartment, she has to close the door,

To open the secret compartment, she has to close the door, open the second draw in her chest,

To open the secret compartment, she has to close the door, open the second draw in her chest, turn her bedside light on.

events doorClosed drawOpened lightOn doorOpened panelClosed end resetEvents doorOpened end commands unlockPanel lockPanel lockDoor unlockDoor end state idle actions {unlockDoor lockPanel} doorClosed => active end state active drawOpened => waitingForLight lightOn => waitingForDraw end state waitingForLight lightOn => unlockedPanel end state waitingForDraw drawOpened => unlockedPanel end state unlockedPanel actions {unlockPanel lockDoor} panelClosed => idle end

External DSL Internal DSL events event :doorClosed doorClosed event :drawOpened drawOpened event :lightOn lightOn doorOpened event :doorOpened panelClosed event :panelClosed end command :unlockPanel resetEvents command :lockPanel doorOpened end command :lockDoor command :unlockDoor commands unlockPanel resetEvents :doorOpened lockPanel lockDoor unlockDoor state :idle do end actions :unlockDoor, :lockPanel transitions :doorClosed => :active state idle end actions {unlockDoor lockPanel} doorClosed => active state :active do end transitions :drawOpened => :waitingForLight, state active :lightOn => :waitingForDraw drawOpened => waitingForLight end lightOn => waitingForDraw end state :waitingForLight do state waitingForLight transitions :lightOn => :unlockedPanel lightOn => unlockedPanel end end state :waitingForDraw do state waitingForDraw transitions :drawOpened => :unlockedPanel drawOpened => unlockedPanel end end state unlockedPanel state :unlockedPanel do actions {unlockPanel lockDoor} actions :unlockPanel, :lockDoor panelClosed => idle transitions :panelClosed => :idle end end

On top of external DSLs no compromises

On top of external DSLs no compromises domain-speciﬁc static analysis

On top of external DSLs no compromises domain-speciﬁc static analysis graphical views

On top of external DSLs no compromises domain-speciﬁc static analysis graphical views closed scope

Implementing an external DSL is complicated

Why not using a DSL ... ... to develop DSLs?

Statemachine : 'events' (events+=Event)+ 'end' 'resetEvents' (resetEvents+=[Event])+ 'end' 'commands' (commands+=Command)+ 'end' (states+=State)+; Event : name=ID; Command : name=ID; State : 'state' name=ID ('actions' '{' (actions+=[Command])+ '}')? (transitions+=Transition)* 'end'; Transition : event=[Event] '=>' state=[State];

Statemachine : 'events' (events+=Event)+ 'end' 'resetEvents' starts with keyword ‘events’ (resetEvents+=[Event])+ 'end' 'commands' (commands+=Command)+ 'end' (states+=State)+; Event : name=ID; Command : name=ID; State : 'state' name=ID ('actions' '{' (actions+=[Command])+ '}')? (transitions+=Transition)* 'end'; Transition : event=[Event] '=>' state=[State];

Statemachine : 'events' (events+=Event)+ 'end' 'resetEvents' followed by at least one (resetEvents+=[Event])+ 'end' definition of Event 'commands' (commands+=Command)+ 'end' (states+=State)+; Event : name=ID; which is defined here and Command : name=ID; consists of just one identifier (ID) State : 'state' name=ID ('actions' '{' (actions+=[Command])+ '}')? (transitions+=Transition)* 'end'; Transition : event=[Event] '=>' state=[State];

Statemachine : 'events' (events+=Event)+ 'end' 'resetEvents' (resetEvents+=[Event])+ 'end' 'commands' (commands+=Command)+ 'end' (states+=State)+; this is a cross reference, Event : referencing Events name=ID; declared in the previous Command : name=ID; section. State : 'state' name=ID ('actions' '{' (actions+=[Command])+ '}')? (transitions+=Transition)* 'end'; Transition : event=[Event] '=>' state=[State];

Statemachine : 'events' (events+=Event)+ 'end' 'resetEvents' (resetEvents+=[Event])+ 'end' 'commands' (commands+=Command)+ 'end' (states+=State)+; Event : name=ID; commands are very Command : similar to events name=ID; State : 'state' name=ID ('actions' '{' (actions+=[Command])+ '}')? (transitions+=Transition)* 'end'; Transition : event=[Event] '=>' state=[State];

Statemachine : 'events' (events+=Event)+ 'end' 'resetEvents' (resetEvents+=[Event])+ 'end' 'commands' (commands+=Command)+ 'end' (states+=State)+; Event : States have a name (ID) name=ID; Command : name=ID; State : 'state' name=ID ('actions' '{' (actions+=[Command])+ '}')? (transitions+=Transition)* 'end'; Transition : event=[Event] '=>' state=[State];

Statemachine : 'events' (events+=Event)+ 'end' 'resetEvents' (resetEvents+=[Event])+ 'end' 'commands' (commands+=Command)+ 'end' (states+=State)+; Event : States have a name (ID) name=ID; Command : name=ID; optional action block State : 'state' name=ID ('actions' '{' (actions+=[Command])+ '}')? (transitions+=Transition)* 'end'; Transition : event=[Event] '=>' state=[State];

Statemachine : 'events' (events+=Event)+ 'end' 'resetEvents' (resetEvents+=[Event])+ 'end' 'commands' (commands+=Command)+ 'end' (states+=State)+; Event : States have a name (ID) name=ID; Command : name=ID; optional action block State : 'state' name=ID ('actions' '{' (actions+=[Command])+ '}')? (transitions+=Transition)* 'end'; Transition : any number of Transitions event=[Event] '=>' state=[State];

This was the example DSL implemented in So what do we get from such a description?

Antlr based Parser

Antlr based Parser Eclipse based Editor

Antlr based Parser Eclipse based Editor Statemachine commands * events * resetStates * states Command State Event name:String * name:String name:String actions state event EMF based Semantic Model * Transition

oaw.itemis.com Thank you very much! the eclipse distro can be downloaded from http://oaw.itemis.com

Xtext @ Profict Summer Camp

by Sven Efftinge on Nov 11, 2008

Accessibility

Categories

Tags

Upload Details

Usage Rights

1 Embed 1

Statistics

Xtext @ Profict Summer Camp — Presentation Transcript