An introduction into Domain Specific Languages with JetBrains MPS presented at GeeCON Prague 2015

1. MPS
Domain Specific Languages
with pleasure
Václav Pech

2. JetBrains MPS
High thoughts must have high language.
Aristophanes

3. Your vocabulary reflects the way you think
Seth Godin

4. [Embedded Software]
mbeddr

5. [Data analysis]
MetaR

6. [Business Application]
Insurance Configuration Tool

7. [Business Application]
Insurance Configuration Tool

8. <no variables> <no parent>
<no libraries>
<no business objects>
<no parent>
[Business Application]
Insurance Configuration Tool

9. Notations for DSLs
● Text
● Diagrams
● Tables
● Forms
● Mixtures of all
● …

10. The number and the type of the basic colour
words of a language determine how one sees the
rain bow

11. Programs are trees
R
A B
C D
G
R
E F

12. Programs are trees
R
A B
C D
G
R
E F

15. Children have roles
R
A IfStatement
Expr StmtList
G
R
E F
condition body

16. References cross the tree
R
Routine def B
Call D
G
R
E F

17. Languages are sets of concepts
C1
C2
C3
Cn
L1
L2

20. Programs and Languages
R
A B
C D
G
R
E F
C1
C2
C3
Cn
L
Models consist of nodes
Meta-models consist of concepts

21. IntelliJ IDEA inspections

22. Groovy AST transformations

23. Groovy AST transformations

26. There's no life without trees
● Extending IDEs
● External DSLs
● Internal DSLs in modern languages
● Groovy AST transformations
● Scala macros
● Lisp, Clojure macros
● Lombok

27. Notations for DSLs
● Text
● Diagrams
● Tables
● Forms
● Mixtures of all
● …

28. Parsing is the bottleneck
… of language expressiveness

29. Editing text
Parsing

30. Programs are trees
R
A B
C D
G
R
E F
WhileLoop
MethodDef
MethodCall
L IfStatement
Models consist of nodes
Meta-models consist of concepts

31. Editing trees directly
Projecting

35. by Jens Nerche @jensnerche
Rich syntaxes

36. Combine languages

37. Multiple notations

38. Parsing is the bottleneck
… of language expressiveness
● Limits the possible syntaxes
● Allows only one editable code visualization
● Complicates combining languages

39. Aspects of language definition
● Abstract syntax
● Concrete syntax (editor)
● Static semantics
● Constraints
● Type-system
● Dataflow
● Execution semantics / Generator
● IDE support

40. Books
● http://books.campagnelab.org
● http://dslbook.org
https://www.jetbrains.com/mps/publications

41. Books
● http://books.campagnelab.org
● http://dslbook.org
← He is a Biologist!
https://www.jetbrains.com/mps/publications

42. The limits of language are the limits of one's world
Ludwig Wittgenstein

43. Questions
Want more?
http://www.jetbrains.com/mps
@vaclav_pech

44. Image credits
http://www.flickr.com/photos/horiavarlan/4329908160/sizes/m/in/photostream/
http://www.flickr.com/photos/pink_floyd/2409134519/sizes/m/in/photostream/
http://www.flickr.com/photos/atache/4124732863/sizes/m/in/photostream/
http://www.flickr.com/photos/a_ninjamonkey/3294014627/sizes/m/in/photostream/
http://www.flickr.com/photos/carlc/1968636137/
http://www.flickr.com/photos/tasuki/3503304405/sizes/m/in/photostream/
http://www.flickr.com/photos/bmwccgb/5069454884/sizes/m/in/photostream/
http://www.flickr.com/photos/rpmarks/3932013183/sizes/m/in/photostream/
http://www.flickr.com/photos/orqwith/4325166853/
https://www.flickr.com/photos/charlestilford/732688216