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serial-lambda
serial-case-lambda
5.3.1 Definition Syntax
define-closure

5.3 Serializable Closures

The defunctionalization process of the Web Language (see Stateless Servlets) requires an explicit representation of closures that is serializable.

(serial-lambda formals body ...)
Returns (lambda formals body ...), except it is serializable.

(serial-case-lambda [formals body ...] ...)
Returns (case-lambda [formals body ...] ...), except it is serializable.

(define-closure tag formals (free-var ...) body)
Defines a closure, constructed with make-tag that accepts a closure that returns freevar ..., that when invoked with formals executes body.

Here is an example:
#lang racket
(require racket/serialize)
 
(define-closure foo (a b) (x y)
 (+ (- a b)
    (* x y)))
 
(define f12 (make-foo (lambda () (values 1 2))))
(serialize f12)
'((1) 1 (('page . foo:deserialize-info)) 0 () () (0 1 2))
(f12 6 7)
1
(f12 9 1)
10
 
(define f45 (make-foo (lambda () (values 4 5))))
(serialize f45)
'((1) 1 (('page . foo:deserialize-info)) 0 () () (0 4 5))
(f45 1 2)
19
(f45 8 8)
20