Bounded Quantification: Why Your Types Need Boundaries Even If You Don't!

"A universal quantifier expresses that a type or function can operate on all types that satisfy a certain bound... this is inherently a contravariant requirement."

"When we write exists T <: Bound. Type, we mean that there exists some specific T that satisfies T <: Bound. We are only guaranteed that T exists somewhere within the bounds but don't know exactly what it is."

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