From aa8769c29dd6e98fd87f1f5aa3a94d73d0cbfccc Mon Sep 17 00:00:00 2001
From: Daniel Ehrenberg <ehrenbed@carleton.edu>
Date: Wed, 13 Feb 2008 20:19:18 -0600
Subject: [PATCH] Making lists into a mixin

---
 extra/lazy-lists/lazy-lists.factor | 67 ++++++++----------------------
 1 file changed, 18 insertions(+), 49 deletions(-)

diff --git a/extra/lazy-lists/lazy-lists.factor b/extra/lazy-lists/lazy-lists.factor
index 1979819dd1..e3e7b14917 100644
--- a/extra/lazy-lists/lazy-lists.factor
+++ b/extra/lazy-lists/lazy-lists.factor
@@ -9,13 +9,10 @@ quotations promises combinators io ;
 IN: lazy-lists
 
 ! Lazy List Protocol
+MIXIN: list
 GENERIC: car   ( cons -- car )
 GENERIC: cdr   ( cons -- cdr )
 GENERIC: nil?  ( cons -- ? )
-GENERIC: list? ( object -- ? )
-
-M: object list? ( object -- bool )
-  drop f ;
 
 M: promise car ( promise -- car )
   force car ;
@@ -26,9 +23,6 @@ M: promise cdr ( promise -- cdr )
 M: promise nil? ( cons -- bool )
   force nil? ;
 
-M: promise list? ( object -- bool )
-  drop t ;
-
 TUPLE: cons car cdr ;
 
 C: cons cons
@@ -45,9 +39,6 @@ M: cons cdr ( cons -- cdr )
 M: cons nil? ( cons -- bool )
     nil eq? ;
 
-M: cons list? ( object -- bool )
-  drop t ;
-
 : 1list ( obj -- cons )
     nil cons ;
 
@@ -74,9 +65,6 @@ M: lazy-cons cdr ( lazy-cons -- cdr )
 M: lazy-cons nil? ( lazy-cons -- bool )
     nil eq? ;
 
-M: lazy-cons list? ( object -- bool )
-  drop t ;
-
 : 1lazy-list ( a -- lazy-cons )
   [ nil ] lazy-cons ;
 
@@ -138,9 +126,6 @@ M: memoized-cons nil? ( memoized-cons -- bool )
     memoized-cons-nil?
   ] if ;
 
-M: memoized-cons list? ( object -- bool )
-  drop t ;
-
 TUPLE: lazy-map cons quot ;
 
 C: <lazy-map> lazy-map
@@ -159,9 +144,6 @@ M: lazy-map cdr ( lazy-map -- cdr )
 M: lazy-map nil? ( lazy-map -- bool )
   lazy-map-cons nil? ;
 
-M: lazy-map list? ( object -- bool )
-  drop t ;
-
 TUPLE: lazy-map-with value cons quot ;
 
 C: <lazy-map-with> lazy-map-with
@@ -182,9 +164,6 @@ M: lazy-map-with cdr ( lazy-map-with -- cdr )
 M: lazy-map-with nil? ( lazy-map-with -- bool )
   lazy-map-with-cons nil? ;
 
-M: lazy-map-with list? ( object -- bool )
-  drop t ;
-
 TUPLE: lazy-take n cons ;
 
 C: <lazy-take> lazy-take
@@ -206,9 +185,6 @@ M: lazy-take nil? ( lazy-take -- bool )
     lazy-take-cons nil?
   ] if ;
 
-M: lazy-take list? ( object -- bool )
-  drop t ;
-
 TUPLE: lazy-until cons quot ;
 
 C: <lazy-until> lazy-until
@@ -226,9 +202,6 @@ M: lazy-until cdr ( lazy-until -- cdr )
 M: lazy-until nil? ( lazy-until -- bool )
    drop f ;
 
-M: lazy-until list? ( lazy-until -- bool )
-   drop t ;
-
 TUPLE: lazy-while cons quot ;
 
 C: <lazy-while> lazy-while
@@ -245,9 +218,6 @@ M: lazy-while cdr ( lazy-while -- cdr )
 M: lazy-while nil? ( lazy-while -- bool )
    [ car ] keep lazy-while-quot call not ;
 
-M: lazy-while list? ( lazy-while -- bool )
-   drop t ;
-
 TUPLE: lazy-subset cons quot ;
 
 C: <lazy-subset> lazy-subset
@@ -285,9 +255,6 @@ M: lazy-subset nil? ( lazy-subset -- bool )
     ] if
   ] if ;
 
-M: lazy-subset list? ( object -- bool )
-  drop t ;
-
 : list>vector ( list -- vector )
   [ [ , ] leach ] V{ } make ;
 
@@ -311,9 +278,6 @@ M: lazy-append cdr ( lazy-append -- cdr )
 M: lazy-append nil? ( lazy-append -- bool )
    drop f ;
 
-M: lazy-append list? ( object -- bool )
-  drop t ;
-
 TUPLE: lazy-from-by n quot ;
 
 C: lfrom-by lazy-from-by ( n quot -- list )
@@ -331,9 +295,6 @@ M: lazy-from-by cdr ( lazy-from-by -- cdr )
 M: lazy-from-by nil? ( lazy-from-by -- bool )
   drop f ;
 
-M: lazy-from-by list? ( object -- bool )
-  drop t ;
-
 TUPLE: lazy-zip list1 list2 ;
 
 C: <lazy-zip> lazy-zip
@@ -351,9 +312,6 @@ M: lazy-zip cdr ( lazy-zip -- cdr )
 M: lazy-zip nil? ( lazy-zip -- bool )
     drop f ;
 
-M: lazy-zip list? ( object -- bool )
-  drop t ;
-
 TUPLE: sequence-cons index seq ;
 
 C: <sequence-cons> sequence-cons
@@ -376,9 +334,6 @@ M: sequence-cons cdr ( sequence-cons -- cdr )
 M: sequence-cons nil? ( sequence-cons -- bool )
     drop f ;
 
-M: sequence-cons list? ( object -- bool )
-  drop t ;
-
 : >list ( object -- list )
   {
     { [ dup sequence? ] [ 0 swap seq>list ] }
@@ -419,9 +374,6 @@ M: lazy-concat nil? ( lazy-concat -- bool )
     drop f
   ] if ;
 
-M: lazy-concat list? ( object -- bool )
-  drop t ;
-
 : lcartesian-product ( list1 list2 -- result )
   swap [ swap [ 2array ] lmap-with ] lmap-with lconcat ;
 
@@ -492,3 +444,20 @@ M: lazy-io cdr ( lazy-io -- cdr )
 
 M: lazy-io nil? ( lazy-io -- bool )
   car not ;
+
+INSTANCE: cons list
+INSTANCE: sequence-cons list
+INSTANCE: memoized-cons list
+INSTANCE: promise list
+INSTANCE: lazy-io list
+INSTANCE: lazy-concat list
+INSTANCE: lazy-cons list
+INSTANCE: lazy-map list
+INSTANCE: lazy-map-with list
+INSTANCE: lazy-take list
+INSTANCE: lazy-append list
+INSTANCE: lazy-from-by list
+INSTANCE: lazy-zip list
+INSTANCE: lazy-while list
+INSTANCE: lazy-until list
+INSTANCE: lazy-subset list