. \(.\) — Binder Scope & Sort Projection Dot (.)
Separates the bound variable from the body in descriptor/lambda binders (ιx. 𝛗, εx. 𝛗, λx. t) and qualifies syntactic expression sorts (Class.Expression, Fm.Expression).
| Field | Mathematical & Kernel Specification (MKTD1 / MKTD2) |
|---|---|
| Symbol |
.
\(.\)
|
| Category | Structural Delimiter |
| SML AST Constructor | Kernel AST Symbol / Sort Constructor in typetheory.ML (Class_p / Truth_p / EXP / UCol) |
| Constructor Arguments | Typed arguments as specified by the Signature / Sort field above |
| Metatype / Signature | Binder Body Separator / Sort Qualification Dot |
| Binder Status | See Category & Signature above |
| Defining Kernel Entries (ML Labels) | See Related Symbols & Kernel Entries below. |
| LaTeX Form | . |
| How to Understand It | Role in Kernel Syntax: Used both as a binder matrix delimiter and as the sort-projection dot in |
| Canonical Law / Usage | (λx. t)(x) = t |
| Related Symbols & Kernel Entries |