;; Standard Library Procedures and Macros ;;
;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
+;; MISC ESSENTIAL PROCEDURES
+
+(define list
+ (lambda args args))
+
+(define map
+ (lambda (proc l)
+ (if (null? l)
+ '()
+ (cons (proc (car l)) (map proc (cdr l))))))
+
+(define join-lists
+ (lambda (l1 l2)
+ (if (null? l1)
+ l2
+ (cons (car l1) (join-lists (cdr l1) l2)))))
+
+; Append an arbitrary number of lists together
+(define append
+ (lambda lists
+ (if (null? lists)
+ ()
+ (if (null? (cdr lists))
+ (car lists)
+ (join-lists (car lists) (apply append (cdr lists)))))))
+
+
;; DERIVED FORMS
-;; define (procedural syntax)
+;; define
(define-macro (define args . body)
(if (pair? args)
- `(define ,(car args) (lambda ,(cdr args) ,@body))
+ (list 'define (car args) (join-lists (list 'lambda (cdr args)) body))
'no-match))
+;; not
+
+(define-macro (not x)
+ (list 'if x #f #t))
+
+;; let
+
+(define-macro (let args . body)
+ (join-lists
+ (list (join-lists (list 'lambda (map (lambda (x) (car x)) args)) body))
+ (map (lambda (x) (car (cdr x))) args)))
+
+;; quasiquote/unquote (one nesting level only)
+
+((lambda ()
+ (define (qqhelper l)
+ (if (null? l)
+ l
+ (let ((head (car l))
+ (tail (cdr l)))
+
+ (if (pair? head)
+ (if (eq? (car head) 'unquote)
+ (list 'cons (car (cdr head)) (qqhelper tail))
+ (if (eq? (car head) 'unquote-splicing)
+ (list 'join-lists (car (cdr head)) (qqhelper tail))
+ (list 'cons (list 'quasiquote head) (qqhelper tail))))
+ (if (symbol? head)
+ (list 'cons (list 'quote head) (qqhelper tail))
+ (list 'cons head (qqhelper tail)))))))
+
+ (define-macro (quasiquote arg)
+ (if (not (pair? arg))
+ (list 'quote arg)
+ (qqhelper arg)))))
+
;; begin
(define-macro (begin . sequence)
(define-macro (cdddr l) `(cdr (cdr (cdr ,l))))
(define-macro (cadddr l) `(car (cdr (cdr (cdr ,l)))))
-
-;; Methods used in remaining macro definitions:
-
-(define (map proc l)
- (if (null? l)
- '()
- (cons (proc (car l)) (map proc (cdr l)))))
-
-;; let
-
-(define-macro (let args . body)
- `((lambda ,(map (lambda (x) (car x)) args)
- ,@body) ,@(map (lambda (x) (cadr x)) args)))
-
;; let*
(define-macro (let* args . body)
(define-macro (and . expressions)
(if (null? expressions)
#t
- (expand-and-expressions expressions)))
- ))
+ (expand-and-expressions expressions)))))
;; or
((lambda ()
(define (expand-or-expressions expressions)
- (if (null? expressions)
- #f
- (let ((first (car expressions))
- (rest (cdr expressions))
- (val (gensym)))
- `(let ((,val ,first))
- (if ,val
- ,val
- ,(expand-or-expressions rest))))))
+ (let ((first (car expressions))
+ (rest (cdr expressions)))
+ (if (null? rest)
+ first
+ `(if ,first
+ #t
+ ,(expand-or-expressions rest)))))
(define-macro (or . expressions)
- (expand-or-expressions expressions))
- ))
-
-;; not
-
-(define-macro (not x)
- `(if ,x #f #t))
+ (if (null? expressions)
+ #f
+ (expand-or-expressions expressions)))))
;; FUNCTIONAL PROGRAMMING
;; LISTS
-; List creation
-(define (list . args) args)
-
; Return number of items in list
(define (length l)
(define (iter a count)
(iter (cdr a) (fix:+ count 1))))
(iter l 0))
-; Join two lists together
-(define (join l1 l2)
- (if (null? l1)
- l2
- (cons (car l1) (join (cdr l1) l2))))
-
-; Append an arbitrary number of lists together
-(define (append . lists)
- (if (null? lists)
- ()
- (if (null? (cdr lists))
- (car lists)
- (join (car lists) (apply append (cdr lists))))))
-
; Reverse the contents of a list
(define (reverse l)
(if (null? l)
(fix:+ n (sum-recurse (fix:- n 1)))))
-
;; MISC
(define (license)
+++ /dev/null
-(define list (lambda args args))
-
-(define join-lists
- (lambda (l1 l2)
- (if (null? l1)
- l2
- (cons (car l1) (join-lists (cdr l1) l2)))))
-
-(define-macro (cadr x) (list 'car (list 'cdr x)))
-
-(define-macro (define args . body)
- (if (pair? args)
- (list 'define (car args) (join-lists (list 'lambda (cdr args)) body))
- 'no-match))
-
-(define (map proc l)
- (if (null? l)
- '()
- (cons (proc (car l)) (map proc (cdr l)))))
-
-
-(define-macro (not x)
- (list 'if x #f #t))
-
-(define-macro (let args . body)
- (join-lists
- (list (join-lists (list 'lambda (map (lambda (x) (car x)) args)) body))
- (map (lambda (x) (cadr x)) args)))
-
-((lambda ()
- (define (qqhelper l)
- (if (null? l)
- l
- (let ((head (car l))
- (tail (cdr l)))
-
- (if (pair? head)
- (if (eq? (car head) 'unquote)
- (list 'cons (cadr head) (qqhelper tail))
- (if (eq? (car head) 'unquote-splicing)
- (list 'join-lists (cadr head) (qqhelper tail))
- (list 'cons (list 'quasiquote head) (qqhelper tail))))
- (if (symbol? head)
- (list 'cons (list 'quote head) (qqhelper tail))
- (list 'cons head (qqhelper tail)))))))
-
- (define-macro (quasiquote arg)
- (if (not (pair? arg))
- (list 'quote arg)
- (qqhelper arg)))))