Strings are Evil: Methods to hide the use of primitive types
summary
Primitive primitives like Int and String cause bugs by allowing invalid domain values; concrete remedies shown include a simple type alias, a case class with a sealed abstract case class wrapper and private constructor to prevent invalid copies, the external library refined which checks literals at compile time and returns Either at runtime for dynamic input, and the upcoming opaque types (SIP) that promise zero runtime overhead; examples include UUIDs validated to 32 hex digits and nonempty strings, and tradeoffs are measured (compile-time checks vs runtime Either and adoption complexity).
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chapters (10)
- 0:00Start
- 0:29Outline
- 4:49Time Zones
- 11:04Runtime Overhead
- 11:58Make the Constructor Private
- 13:52Sealed Abstract Case Class Uid
- 16:34Functions
- 25:36Opaque Types
- 28:08Summary
- 29:46Refinement Types
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