From 75db8bed918453455045cc5d4dabb83a068e674e Mon Sep 17 00:00:00 2001
From: Jan Nieuwenhuizen <janneke@gnu.org>
Date: Sun, 29 Apr 2018 18:29:26 +0200
Subject: [PATCH] mes: filter-map: Handle two lists.

* module/srfi/srfi-1.mes (filter-map): Handle two lists, add error
  when called with three or more.
---
 module/mes/base.mes    | 20 ++++++++++----------
 module/srfi/srfi-1.mes | 16 +++++++++++-----
 2 files changed, 21 insertions(+), 15 deletions(-)

diff --git a/module/mes/base.mes b/module/mes/base.mes
index 704ea566..51d0f488 100644
--- a/module/mes/base.mes
+++ b/module/mes/base.mes
@@ -107,13 +107,13 @@
         ((closure? p) #t)
         (#t #f)))
 
-(define (map f l . r)
-  (if (null? l) '()
-      (if (null? r) (cons (f (car l)) (map f (cdr l)))
-          (if (null? (cdr r))
-              (cons (f (car l) (caar r)) (map f (cdr l) (cdar r)))
-              (if (null? (cddr r))
-                  (cons (f (car l) (caar r) (caadr r)) (map f (cdr l) (cdar r) (cdadr r)))
-                  (if (null? (cdddr r))
-                      (cons (f (car l) (caar r) (caadr r) (car (caddr r))) (map f (cdr l) (cdar r) (cdadr r) (cdr (caddr r))))
-                      (error 'unsupported (cons* "map 5:" f l r))) )))))
+(define (map f h . t)
+  (if (null? h) '()
+      (if (null? t) (cons (f (car h)) (map f (cdr h)))
+          (if (null? (cdr t))
+              (cons (f (car h) (caar t)) (map f (cdr h) (cdar t)))
+              (if (null? (cddr t))
+                  (cons (f (car h) (caar t) (caadr t)) (map f (cdr h) (cdar t) (cdadr t)))
+                  (if (null? (cdddr t))
+                      (cons (f (car h) (caar t) (caadr t) (car (caddr t))) (map f (cdr h) (cdar t) (cdadr t) (cdr (caddr t))))
+                      (error 'unsupported (cons* "map 5:" f h t))) )))))
diff --git a/module/srfi/srfi-1.mes b/module/srfi/srfi-1.mes
index 321a47f5..d5103390 100644
--- a/module/srfi/srfi-1.mes
+++ b/module/srfi/srfi-1.mes
@@ -40,11 +40,17 @@
 (define (append-map f lst . rest)
   (apply append (apply map f (cons lst rest))))
 
-(define (filter-map f lst)
-  (if (null? lst) (list)
-      (let ((r (f (car lst))))
-        (if r (cons r (filter-map f (cdr lst)))
-            (filter-map f (cdr lst))))))
+(define (filter-map f h . t)
+  (if (null? h) '()
+      (if (null? t)
+          (let ((r (f (car h))))
+            (if r (cons r (filter-map f (cdr h)))
+                (filter-map f (cdr h))))
+          (if (null? (cdr t))
+              (let ((r (f (car h) (caar t))))
+                (if r (cons r (filter-map f (cdr h) (cdar t)))
+                    (filter-map f (cdr h) (cdar t))))
+              (error 'unsupported (cons* "filter-map 3:" f h t))))))
 
 ;;; nyacc requirements