(define-library (substratic engine macros)

(import (gambit))

(export -> ->>)

(begin

;; This module contains generally useful macros that might be moved out into

;; a separate library (and re-exported here) at a later date.

(define-macro (-> . forms)

(let ((result-sym (gensym 'pipeline-)))

`(let ((,result-sym ,(car forms)))

,@(map (lambda (form)

`(set! ,result-sym ,(append (list (car form)) (list result-sym) (cdr form))))

(cdr forms))

,result-sym)))

(define-macro (->> . forms)

(let ((result-sym (gensym 'pipeline-)))

`(let ((,result-sym ,(car forms)))

,@(map (lambda (form)

`(set! ,result-sym ,(append form (list result-sym))))

(cdr forms))

,result-sym)))))