identifier-syntax

[syntax] identifier-syntax tmpl

[syntax] identifier-syntax (id1 tmpl1) ((set! id2 e2) tmpl2)

R6RS, ChezScheme

From R6RS examples:

define p (cons 4 5))
(define-syntax p.car (identifier-syntax (car p)))
p.car         => 4
(set! p.car 15)         =>  &syntax exception

(define p (cons 4 5))
(define-syntax p.car
  (identifier-syntax
    (_ (car p))
    ((set! _ e) (set-car! p e))))
(set! p.car 15)
p.car                   => 15
p                       => (15 5)

See also syntax-rules, syntax-case