Part 1
Cats Core, Part 1: From Optional Fields to Useful Validation Errors
I started learning Cats Core with a small policy form. The same mapN operation first combines optional fields, then collects useful validation errors with Validated.
Series
Cats Core
Learning Typelevel Cats Core in Scala 2 through runnable examples: combining optional values, collecting validation errors, and understanding the type classes behind practical operations.
Next in this series: Combining values with Semigroup — coming soon.