compile/let

Symbol: compile/let

Syntax:

• Unnamed: (let BINDINGS BODY ...)

• Named: (let NAME BINDINGS BODY ...)

Bindings: A list of binding forms; each is [SYM EXPR] or (EXPR as: SYM). Parsed with gather_bindings (see helpers). Matcher shape: BINDINGS with koskari.matcher.

Use-case: Lexical bindings for the duration of the body. Unnamed let pushes a child namespace (PUSH_NS), binds names to compiled values, runs the body, and pops (POP_NS). Named let expands to an immediately-invoked named lambda: ((lambda NAME [args...] BODY...) val...), so the name is bound in the function’s scope for recursion.

Behaviour: Unnamed: child_namespace with the binding names and value expressions; body compiled with helper_begin. Named: rewrite to ((lambda NAME [args...] BODY...) val...) via pycons.

Examples:

;; Unnamed let
(let [[x 1] [y 2]] (+ x y))

;; Named let (e.g. loop)
(let loop [[n 10]]
  (loop ...))