proper \(\mathrm{proper}\) — Proper Class Predicate (proper, AST Constructor: TpProper)
Unary predicate K proper asserting that class K is not a set: ¬(K set) (Entry DefIsProperClass (3.03)).
| Field | Mathematical & Kernel Specification (MKTD1 / MKTD2) |
|---|---|
| Symbol |
proper
\(\mathrm{proper}\)
|
| Category | Predicate Symbol (Unary Class Predicate) |
| SML AST Constructor | HP (TpProper of 'Class_EXP) [in datatype Truth_p, typetheory.ML:662] |
| Constructor Arguments | 1. Class term K : Class |
| Metatype / Signature | Class → Bool |
| Binder Status | No — Defined Unary Predicate Symbol (Proper Class) |
| Defining Kernel Entries (ML Labels) | See Related Symbols & Kernel Entries below. |
| LaTeX Form | \mathrm{proper} |
| How to Understand It | SML AST Constructor: |
| Canonical Law / Usage | ∀(K:Class)((K proper) ⟷ (¬(K set))) |
| Related Symbols & Kernel Entries |