[image error] No Naked Primitives is a Coderetreat constraint which trains our object orientation skills. No primitive values, e.g. booleans, numbers or strings, must be visible at object boundaries, i.e. public methods. Arrays and other containers like lists or hash-tables are primitives, too. I love this constraint, as it pushes people right out of their comfort zone. ;-) (I wrote about No Naked Primitives in combination with other constraints and included it in the expert level Brutal Coding Constraints.)

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