Next Level DSLs

Configure your app the Kotlin way!

Aaron will walk you through the design of a pluggable app architecture, all driven by an expansive domain-specific language executed at run-time.

Heavily inspired by the structure of build.gradle, this talk will demonstrate how you can push your configuration logic into a type-safe, declarative, and convenient format.

Source Code: https://gitlab.com/asarazan/kotlinconf18

Transcript

1. https://gitlab.com/asarazan/kotlinconf18 Next Level DSLs Configure your app the Kotlin way!
2. Next Level DSLs Configure your app the Kotlin way!
3. Next Level DSLs Configure your app the Kotlin way!
7. Isolated Feature Development
8. A Plugin It’s like an app, just smaller
9. Android Manifest
10. Plugin DSL
11. Plugin DSL
12. Plugin DSL
13. Plugin DSL
14. Plugin DSL
15. Back to Basics
16. Help! What’s a DSL?
17. When you really wish your language could do the thing.
18. Help! What’s a DSL? Java
19. Help! What’s a DSL? LISP
20. Help! What’s a DSL? Ruby
21. Podfiles
22. Help! What’s a DSL? Domain Specific Language
23. white space
24. Help! What’s a DSL? Domain Specific Language
26. Help! What’s a DSL? Domain Specific Language
27. Help! What’s a DSL? Domain Specific Language
28. Help! What’s a DSL? Domain Specific Language
29. You don’t DO the thing. You STATE the thing.
30. GRADLE!
31. Here’s How It Works
32. Here’s How It Works
35. Here’s How It Works
36. Here’s How It Works
37. Experience Get!
38. When Should I Make a DSL?
39. Anko
40. Anko
41. Anko
42. This is Really Unpleasant ...and there has to be a better way. • XML • Configuration • Declaration • Boilerplate • Builders
43. Builders ALWAYS a candidate for DSLs
44. Readability
45. Work Backwards Start from the result that you want to enable ...then write the code that enables it!
46. Start With Builders Immutability with a side of Java-friendliness!
47. @DslMarker Prevent Scoping Mishaps!
48. Good Hygiene • Don’t pollute the global namespace • Unary “+” only if well-scoped • Keep Lambda files next to your builder classes ◦ Plugin.kt ◦ PluginLambdas.kt • Don’t extend system types ◦ String, Int, etc.
49. Good Hygiene • Don’t pollute the global namespace • Unary “+” only if well-scoped • Keep Lambda files next to your builder classes ◦ Plugin.kt ◦ PluginLambdas.kt • Don’t extend system types ◦ String, Int, etc.
50. Good Hygiene • Don’t pollute the global namespace • Unary “+” only if well-scoped • Keep Lambda files next to your builder classes ◦ Plugin.kt ◦ PluginLambdas.kt • Don’t extend system types ◦ String, Int, etc. • Have fun!
51. Thank You aaron@stencil.ltd https://gitlab.com/asarazan/kotlinconf18