X-Git-Url: http://git.kpe.io/?a=blobdiff_plain;f=lists.lisp;h=77b6fa52401157e11b78451156903100a4df6775;hb=4c379c22b88b4433ed56fd8665e1265442b10ee2;hp=6b0edb27b7550344f33ed1826fc70d4b531936cf;hpb=d3a88acfecf83fc695ca7b6e247ec735c85625bf;p=kmrcl.git

diff --git a/lists.lisp b/lists.lisp
index 6b0edb2..77b6fa5 100644
--- a/lists.lisp
+++ b/lists.lisp
@@ -7,7 +7,7 @@
 ;;;; Programmer:    Kevin M. Rosenberg
 ;;;; Date Started:  Apr 2000
 ;;;;
-;;;; $Id: lists.lisp,v 1.4 2003/05/11 21:51:43 kevin Exp $
+;;;; $Id: lists.lisp,v 1.9 2003/07/31 07:32:11 kevin Exp $
 ;;;;
 ;;;; This file, part of KMRCL, is Copyright (c) 2002 by Kevin M. Rosenberg
 ;;;;
@@ -16,19 +16,25 @@
 ;;;; (http://opensource.franz.com/preamble.html), also known as the LLGPL.
 ;;;; *************************************************************************
 
-(in-package :kmrcl)
-
+(in-package #:kmrcl)
 
 (defun mklist (obj)
   "Make into list if atom"
   (if (listp obj) obj (list obj)))
 
+(defun map-and-remove-nils (fn lst)
+  "mao a list by function, eliminate elements where fn returns nil"
+  (let ((acc nil))
+    (dolist (x lst (nreverse acc))
+      (let ((val (funcall fn x)))
+        (when val (push val acc))))))
+
 (defun filter (fn lst)
   "Filter a list by function, eliminate elements where fn returns nil"
   (let ((acc nil))
     (dolist (x lst (nreverse acc))
-      (let ((val (funcall fn x)))
-        (if val (push val acc))))))
+      (when (funcall fn x)
+        (push x acc)))))
 
 (defun appendnew (l1 l2)
   "Append two lists, filtering out elem from second list that are already in first list"
@@ -128,3 +134,53 @@
     (dolist (elem (cdr list) results)
       (setq results (append results elem)))))
 
+
+;; alists and plists
+
+(defun alist-elem-p (elem)
+  (and (consp elem) (atom (car elem)) (atom (cdr elem))))
+
+(defun alistp (alist)
+  (when (listp alist)
+    (dolist (elem alist)
+      (unless (alist-elem-p elem)
+        (return-from alistp nil)))
+    t))
+
+(defmacro update-alist (akey value alist &key (test '#'eql) (key '#'identity))
+  "Macro to support below (setf get-alist)"
+  (let ((elem (gensym)))
+    `(let ((,elem (assoc ,akey ,alist :test ,test :key ,key)))
+       (if ,elem
+	   (progn
+	     (setf (cdr ,elem) ,value)
+	     ,alist)
+	(setf ,alist (acons ,akey ,value ,alist))))))
+
+(defun get-alist (key alist &key (test #'eql))
+  (cdr (assoc key alist :test test)))
+
+(defun (setf get-alist) (value key alist &key (test #'eql))
+  (update-alist key value alist :test test)
+  value)
+
+(defun alist-plist (alist)
+  (apply #'append (mapcar #'(lambda (x) (list (car x) (cdr x))) alist)))
+
+(defun plist-alist (plist)
+  (do ((alist '())
+       (pl plist (cddr plist)))
+      ((null pl) alist)
+    (setq alist (acons (car pl) (cadr pl) alist))))
+
+(defmacro update-plist (pkey value plist &key (test '#'eql))
+  "Macro to support below (setf get-alist)"
+  (let ((pos (gensym)))
+    `(let ((,pos (member ,pkey ,plist :test ,test)))
+       (if ,pos
+	   (progn
+	     (setf (cadr ,pos) ,value)
+	     ,plist)
+	 (setf ,plist (append ,plist (list ,pkey ,value)))))))
+
+