Added macro expansion skeleton.

[scheme.forth.jl.git] / src / scheme-library.scm

diff --git a/src/scheme-library.scm b/src/scheme-library.scm
index 14aa6f8..a420c70 100644 (file)
--- a/src/scheme-library.scm
+++ b/src/scheme-library.scm
@@ -12,8 +12,34 @@
 (define (cadr l) (car (cdr l)))
 (define (cdar l) (cdr (car l)))
 (define (cddr l) (cdr (cdr l)))
 (define (cadr l) (car (cdr l)))
 (define (cdar l) (cdr (car l)))
 (define (cddr l) (cdr (cdr l)))

+(define (caaar l) (car (car (car l))))
+(define (caadr l) (car (car (cdr l))))

 (define (cadar l) (car (cdr (car l))))
 (define (cadar l) (car (cdr (car l))))

+(define (caddr l) (car (cdr (cdr l))))
+(define (cdaar l) (cdr (car (car l))))
+(define (cdadr l) (cdr (car (cdr l))))
+(define (cddar l) (cdr (cdr (car l))))
+(define (cdddr l) (cdr (cdr (cdr l))))
+(define (cadddr l) (car (cdr (cdr (cdr l)))))

 
 

+;; FUNCTIONAL PROGRAMMING
+
+(define (fold-left proc init l)
+  (if (null? l)
+    init
+    (fold-left proc (proc init (car l)) (cdr l))))
+
+(define (reduce-left proc init l)
+  (if (null? l)
+    init
+    (if (null? (cdr l))
+      (car l)
+      (fold-left proc (proc (car l) (car (cdr l))) (cdr (cdr l))))))
+
+(define (map proc l)
+  (if (null? l)
+    '()
+    (cons (proc (car l)) (map proc (cdr l)))))

 
 ;; NUMBERS
 
 
 ;; NUMBERS
 


@@ -118,18 +144,6 @@
 (define (null? arg)
   (eq? arg '()))
 
 (define (null? arg)
   (eq? arg '()))
 

-(define (fold-left proc init l)
-  (if (null? l)
-    init
-    (fold-left proc (proc init (car l)) (cdr l))))
-
-(define (reduce-left proc init l)
-  (if (null? l)
-    init
-    (if (null? (cdr l))
-      (car l)
-      (fold-left proc (proc (car l) (car (cdr l))) (cdr (cdr l))))))
-

 (define (+ . args)
   (fold-left pair+ 0 args))
 
 (define (+ . args)
   (fold-left pair+ 0 args))
 


@@ -195,6 +209,10 @@
 (define (integer? x) (= x (round x)))
 (define (exact? x) (fixnum? x))
 (define (inexact? x) (flonum? x))
 (define (integer? x) (= x (round x)))
 (define (exact? x) (fixnum? x))
 (define (inexact? x) (flonum? x))

+(define (number? x)
+  (if (fixnum? x) #t
+    (if (flonum? x) #t
+      (if (ratnum? x) #t #f))))

 
 ;; LISTS
 
 
 ;; LISTS
 


@@ -231,19 +249,17 @@
 
 ; let
 
 
 ; let
 

-(define (let-vars args)
-  (if (null? args)
-    '()
-    (cons (caar args) (let-vars (cdr args)))))
+(define-macro (let args . body)
+              `((lambda ,(map (lambda (x) (car x)) args)
+                 ,@body) ,@(map (lambda (x) (cadr x)) args)))

 
 

-(define (let-inits args)
-  (if (null? args)
-    '()
-  (cons (cadar args) (let-inits (cdr args)))))
+; let*

 
 

-(define-macro (let args . body)
-              `((lambda ,(let-vars args)
-                 ,@body) ,@(let-inits args)))
+(define-macro (let* args . body)
+              (if (null? args)
+                `(let () ,@body)
+                `(let (,(car args))
+                   (let* ,(cdr args) ,@body))))

 
 ; while
 
 
 ; while
 


@@ -257,60 +273,66 @@
 
 ; cond
 
 
 ; cond
 

-(define (cond-predicate clause) (car clause))
-(define (cond-actions clause) (cdr clause))
-(define (cond-else-clause? clause)
-  (eq? (cond-predicate clause) 'else))
-
-(define (expand-clauses clauses)
-  (if (null? clauses)
-    (none)
-    (let ((first (car clauses))
-          (rest (cdr clauses)))
-      (if (cond-else-clause? first)
-        (if (null? rest)
-          `(begin ,@(cond-actions first))
-          (error "else clause isn't last in cond expression."))
-        `(if ,(cond-predicate first)
-           (begin ,@(cond-actions first))
-           ,(expand-clauses rest))))))
-
-(define-macro (cond . clauses)
-              (if (null? clauses)
-                (error "cond requires at least one clause.")
-                (expand-clauses clauses)))
+((lambda ()
+   (define (cond-predicate clause) (car clause))
+   (define (cond-actions clause) (cdr clause))
+   (define (cond-else-clause? clause)
+     (eq? (cond-predicate clause) 'else))
+
+   (define (expand-clauses clauses)
+     (if (null? clauses)
+       (none)
+       (let ((first (car clauses))
+             (rest (cdr clauses)))
+         (if (cond-else-clause? first)
+           (if (null? rest)
+             `(begin ,@(cond-actions first))
+             (error "else clause isn't last in cond expression."))
+           `(if ,(cond-predicate first)
+              (begin ,@(cond-actions first))
+              ,(expand-clauses rest))))))
+
+   (define-macro (cond . clauses)
+                 (if (null? clauses)
+                   (error "cond requires at least one clause.")
+                   (expand-clauses clauses)))
+   ))

 
 ; and
 
 
 ; and
 

-(define (expand-and-expressions expressions)
-  (let ((first (car expressions))
-        (rest (cdr expressions)))
-    (if (null? rest)
-      first
-      `(if ,first
-         ,(expand-and-expressions rest)
-         #f))))
-
-(define-macro (and . expressions)
-              (if (null? expressions)
-                #t
-                (expand-and-expressions expressions)))
+((lambda ()
+   (define (expand-and-expressions expressions)
+     (let ((first (car expressions))
+           (rest (cdr expressions)))
+       (if (null? rest)
+         first
+         `(if ,first
+            ,(expand-and-expressions rest)
+            #f))))
+
+   (define-macro (and . expressions)
+                 (if (null? expressions)
+                   #t
+                   (expand-and-expressions expressions)))
+   ))

 
 ; or
 
 
 ; or
 

-(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))))))
-
-(define-macro (or . expressions)
-              (expand-or-expressions expressions))
+((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))))))
+
+   (define-macro (or . expressions)
+                 (expand-or-expressions expressions))
+   ))

 
 
 ;; TESTING
 
 
 ;; TESTING