- ; basic list accessors
-
+;
+; Copyright © 2016 Keith Packard <keithp@keithp.com>
+;
+; This program is free software; you can redistribute it and/or modify
+; it under the terms of the GNU General Public License as published by
+; the Free Software Foundation, either version 2 of the License, or
+; (at your option) any later version.
+;
+; This program is distributed in the hope that it will be useful, but
+; WITHOUT ANY WARRANTY; without even the implied warranty of
+; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+; General Public License for more details.
+;
+; Lisp code placed in ROM
-(setq cadr (lambda (l) (car (cdr l))))
-(setq caddr (lambda (l) (car (cdr (cdr l)))))
-(setq list (lexpr (l) l))
+ ; return a list containing all of the arguments
- ; evaluate a list of sexprs
+(set (quote list) (lexpr (l) l))
-(setq progn (lexpr (l) (last l)))
-
- ; simple math operators
-
-(setq 1+ (lambda (x) (+ x 1)))
-(setq 1- (lambda (x) (- x 1)))
-
- ; define a variable without returning the value
+ ;
+ ; Define a variable without returning the value
+ ; Useful when defining functions to avoid
+ ; having lots of output generated
+ ;
-(set 'def (macro (def-param)
+(setq def (macro (name val rest)
(list
'progn
(list
'set
- (list
- 'quote
- (car def-param))
- (cadr def-param)
- )
+ (list 'quote name)
+ val)
+ (list 'quote name)
+ )
+ )
+ )
+
+ ;
+ ; A slightly more convenient form
+ ; for defining lambdas.
+ ;
+ ; (defun <name> (<params>) s-exprs)
+ ;
+
+(def defun (macro (name args exprs)
(list
- 'quote
- (car def-param)
+ def
+ name
+ (cons 'lambda (cons args exprs))
)
)
- )
)
+ ; basic list accessors
+
+
+(defun cadr (l) (car (cdr l)))
+
+(defun caddr (l) (car (cdr (cdr l))))
+
+(defun nth (list n)
+ (cond ((= n 0) (car list))
+ ((nth (cdr list) (1- n)))
+ )
+ )
+
+ ; simple math operators
+
+(defun 1+ (x) (+ x 1))
+(defun 1- (x) (- x 1))
+
; define a set of local
; variables and then evaluate
; a list of sexprs
;
; (let ((x 1) (y)) (setq y (+ x 1)) y)
-(def let (macro (let-param)
- ((lambda (vars exprs make-names make-exprs make-nils)
- (progn
+(def let (macro (vars exprs)
+ ((lambda (make-names make-exprs make-nils)
;
; make the list of names in the let
;
- (set 'make-names (lambda (vars)
- (cond (vars
- (cons (car (car vars))
- (make-names (cdr vars))))
- )
- )
- )
- ;
+ (setq make-names (lambda (vars)
+ (cond (vars
+ (cons (car (car vars))
+ (make-names (cdr vars))))
+ )
+ )
+ )
+
; the set of expressions is
; the list of set expressions
; pre-pended to the
; expressions to evaluate
- ;
- (set 'make-exprs (lambda (vars exprs)
- (progn
- (cond (vars (cons
- (list set
- (list quote
- (car (car vars))
- )
- (cadr (car vars))
- )
- (make-exprs (cdr vars) exprs)
- )
- )
- (exprs)
- )
- )
- )
- )
- (set 'exprs (make-exprs vars exprs))
- ;
- ; the parameters to the lambda is a list
- ; of nils of the right length
- ;
- (set 'make-nils (lambda (vars)
- (cond (vars (cons nil (make-nils (cdr vars))))
+ (setq make-exprs (lambda (vars exprs)
+ (cond (vars (cons
+ (list set
+ (list quote
+ (car (car vars))
+ )
+ (cadr (car vars))
+ )
+ (make-exprs (cdr vars) exprs)
+ )
+ )
+ (exprs)
)
)
- )
- ;
+ )
+
+ ; the parameters to the lambda is a list
+ ; of nils of the right length
+
+ (setq make-nils (lambda (vars)
+ (cond (vars (cons nil (make-nils (cdr vars))))
+ )
+ )
+ )
+ ; prepend the set operations
+ ; to the expressions
+
+ (setq exprs (make-exprs vars exprs))
+
; build the lambda.
- ;
- (set 'last-let-value
- (cons
- (list
- 'lambda
- (make-names vars)
- (cond ((cdr exprs) (cons 'progn exprs))
- ((car exprs))
- )
- )
- (make-nils vars)
- )
- )
- )
-
+
+ (cons (cons 'lambda (cons (make-names vars) exprs))
+ (make-nils vars)
+ )
)
- (car let-param)
- (cdr let-param)
()
()
()
)
)
)
+
+ ; boolean operators
+
+(def or (lexpr (l)
+ (let ((ret nil))
+ (while l
+ (cond ((setq ret (car l))
+ (setq l nil))
+ ((setq l (cdr l)))))
+ ret
+ )
+ )
+ )
+
+ ; execute to resolve macros
+
+(or nil t)
+
+(def and (lexpr (l)
+ (let ((ret t))
+ (while l
+ (cond ((setq ret (car l))
+ (setq l (cdr l)))
+ ((setq ret (setq l nil)))
+ )
+ )
+ ret
+ )
+ )
+ )
+
+ ; execute to resolve macros
+
+(and t nil)