;;;; condition-utils.inline.scm  -*- Scheme -*-
;;;; Kon Lovett, Jan '25

(define-type condition-predicate (* -> boolean : condition))
(define-type condition-property-accessor (condition -> *))

;NOTE really on1st/1!

#;
(define-syntax on1st
  (syntax-rules ()
    ((on1st ?typ ?e0 ...)
      (let ((+proc+ (the (or false ?typ) #f)))
        (lambda (x)
          (unless +proc+ (set! +proc+ (begin ?e0 ...)))
          (+proc+ x)) ) ) ) )

(define-syntax on1st
  (syntax-rules ()
    ((on1st ?nam ?typ ?e0 ...)
      (begin
        (: ?nam ?typ)
        (let ((+proc+ (the (or false ?typ) #f)))
          (lambda (x)
            (unless +proc+
              (let ((+proc+ (begin ?e0 ...)))
                (set! ?nam +proc+)
                (+proc+ x)) ) ) ) ) ) ) )

(define-syntax define-condition-predicate
  (syntax-rules ()
    ((define-condition-predicate ?nam ?d0 ...)
      (define ?nam
        (on1st ?nam condition-predicate (make-condition-predicate ?d0 ...))) ) ) )

(define-syntax define-condition-property-accessor
  (syntax-rules ()
    ((define-condition-property-accessor ?nam ?d0 ...)
      (define ?nam
        (on1st ?nam condition-property-accessor (make-condition-property-accessor ?d0 ...))) ) ) )