This exercise should provide a boilerplate with already implemented functions that only need a type declaration. The functions should be simple so that the exercise can appear early in the concept tree. The instructions should clearly express that it is all about native PHP type declarations, not comments (PHPDoc or phpstan/psalm types).
- property types
- method parameter types
- method return types
- type unions
- phpstan/psalm types
integersfloating-point-numbersstringsbooleansarraysclass-basics
type-declarations