--- gforth/glocals.fs	2011/12/27 16:38:08	1.62
+++ gforth/glocals.fs	2012/02/09 17:27:37	1.67
@@ -1,6 +1,6 @@
 \ A powerful locals implementation
 
-\ Copyright (C) 1995,1996,1997,1998,2000,2003,2004,2005,2007 Free Software Foundation, Inc.
+\ Copyright (C) 1995,1996,1997,1998,2000,2003,2004,2005,2007,2011 Free Software Foundation, Inc.
 
 \ This file is part of Gforth.
 
@@ -79,19 +79,10 @@
 \ aligned correctly, but our locals stack must be float-aligned between
 \ words.
 
-\ Other things about the internals are pretty unclear now.
-
-\ Currently locals may only be
-\ defined at the outer level and TO is not supported.
-
 require search.fs
 require float.fs
 require extend.fs \ for case
 
-: save-mem-dict ( addr1 u -- addr2 u )
-    here swap dup allot ( addr1 addr2 u )
-    2dup 2>r move 2r> ;
-
 : compile-@local ( n -- ) \ gforth compile-fetch-local
  case
     0       of postpone @local0 endof
@@ -174,28 +165,62 @@ variable locals-mem-list \ linked list o
 
 \ locals list operations
 
-: common-list ( list1 list2 -- list3 ) \ gforth-internal
-\ list1 and list2 are lists, where the heads are at higher addresses than
-\ the tail. list3 is the largest sublist of both lists.
- begin
-   2dup u<>
- while
-   2dup u>
-   if
-     swap
-   then
-   @
- repeat
- drop ;
-
-: sub-list? ( list1 list2 -- f ) \ gforth-internal
-\ true iff list1 is a sublist of list2
- begin
-   2dup u<
- while
-   @
- repeat
- = ;
+: list-length ( list -- u )
+    0 swap begin ( u1 list1 )
+	dup while
+	    @ swap 1+ swap
+    repeat
+    drop ;
+
+: /list ( list1 u -- list2 )
+    \ list2 is list1 with the first u elements removed
+    0 ?do
+	@
+    loop ;
+
+: common-list ( list1 list2 -- list3 )
+    \ list3 is the largest common tail of both lists.
+    over list-length over list-length - dup 0< if
+	negate >r swap r>
+    then ( long short u )
+    rot swap /list begin ( list3 list4 )
+	2dup u<> while
+	    @ swap @
+    repeat
+    drop ;
+
+: sub-list? ( list1 list2 -- f )
+    \ true iff list1 is a sublist of list2
+    over list-length over list-length swap - 0 max /list = ;
+
+\ : ocommon-list ( list1 list2 -- list3 ) \ gforth-internal
+\ \ list1 and list2 are lists, where the heads are at higher addresses than
+\ \ the tail. list3 is the largest sublist of both lists.
+\  begin
+\    2dup u<>
+\  while
+\    2dup u>
+\    if
+\      swap
+\    then
+\    @
+\  repeat
+\  drop ;
+
+\ : osub-list? ( list1 list2 -- f ) \ gforth-internal
+\ \ true iff list1 is a sublist of list2
+\  begin
+\    2dup u<
+\  while
+\    @
+\  repeat
+\  = ;
+
+\ defer common-list
+\ defer sub-list?
+
+\ ' ocommon-list is common-list
+\ ' osub-list?   is sub-list?
 
 : list-size ( list -- u ) \ gforth-internal
     \ size of the locals frame represented by list
@@ -217,7 +242,7 @@ variable locals-mem-list \ linked list o
 \ warn if list is not a sublist of locals-list
  locals-list @ sub-list? 0= if
    \ !! print current position
-   ." compiler was overly optimistic about locals at a BEGIN" cr
+     >stderr ." compiler was overly optimistic about locals at a BEGIN" cr
    \ !! print assumption and reality
  then ;
 
@@ -542,12 +567,15 @@ forth definitions
     latest latestxt
     clear-leave-stack
     0 locals-size !
-    locals-mem-list @ free-list
-    0 locals-mem-list !
     0 locals-list !
     dead-code off
     defstart ;
 
+:noname ( -- )
+    locals-mem-list @ free-list
+    0 locals-mem-list ! ;
+is free-old-local-names
+
 : locals-;-hook ( sys addr xt sys -- sys )
     def?
     0 TO locals-wordlist
@@ -627,6 +655,7 @@ forth definitions
 ' locals-:-hook IS :-hook
 ' locals-;-hook IS ;-hook
 
+
 ' (then-like)  IS then-like
 ' (begin-like) IS begin-like
 ' (again-like) IS again-like