Language Design: Typing Terminology
Most people think only in terms of the dichotomy between Nominal-Manifest-Static-Strong and Structural-Inferred-Dynamic-Weak in any given discussion of programming language type system design. And it is exhausting.
Most individual distinction are a scale, not a strict yes/no checkbox.
Static ⟷ Dynamic (Typing Modality/Presence)
It refers to what mode of the program it exists in, the analysis stage (where you get e.g. syntax errors too) or the execution stage. More Static: Haskell, CommonLisp, More Dynamic: SmallTalk, Scheme
Manifest ⟷ Inferred (Typing Apparency)
It describes the degree to which types need to mentioned in the program text.
More Manifest: Java, C, More Inferred: Python, Haskell.
Nominal ⟷ Structural (Typing Morphology)
It pertains to how types are described and referred to and when they are judged equal.
More Nominal: Rust, D, More Structural: Ruby, OCaml.
→ Mention Java SAM types.
Reified ⟷ Erased (Typing Preservation)
reification: runtime- vs. user-exposed?
Compile-time vs. Run-time Reflection?
Not directly typing related, but typing preservation choices have a direct impact on what’s possible. (Maybe as sub-point of reified vs. erased?)
Tagged ⟷ Untagged
→ cite Benjamin Pierce → cite Bob Harper
Not really typing:
Strong ⟷ Weak (Typing Discipline/Value Convertibility)