--- gforth/extend.fs	2002/12/27 12:32:52	1.50
+++ gforth/extend.fs	2011/08/10 13:55:02	1.68
@@ -1,12 +1,12 @@
 \ EXTEND.FS    CORE-EXT Word not fully tested!         12may93jaw
 
-\ Copyright (C) 1995,1998,2000 Free Software Foundation, Inc.
+\ Copyright (C) 1995,1998,2000,2003,2005,2007,2009,2010 Free Software Foundation, Inc.
 
 \ This file is part of Gforth.
 
 \ Gforth 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
+\ as published by the Free Software Foundation, either version 3
 \ of the License, or (at your option) any later version.
 
 \ This program is distributed in the hope that it will be useful,
@@ -15,8 +15,7 @@
 \ GNU General Public License for more details.
 
 \ You should have received a copy of the GNU General Public License
-\ along with this program; if not, write to the Free Software
-\ Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111, USA.
+\ along with this program. If not, see http://www.gnu.org/licenses/.
 
 
 \ May be cross-compiled
@@ -36,10 +35,12 @@ decimal
 
 \ !! 2value
 
+[ifundef] 2literal
 : 2Literal ( compilation w1 w2 -- ; run-time  -- w1 w2 ) \ double two-literal
     \G Compile appropriate code such that, at run-time, cell pair @i{w1, w2} are
     \G placed on the stack. Interpretation semantics are undefined.
     swap postpone Literal  postpone Literal ; immediate restrict
+[then]
 
 ' drop alias d>s ( d -- n ) \ double		d_to_s
 
@@ -48,8 +49,12 @@ decimal
     \G In ANS Forth u3 can only be a positive signed number.
     >r s>d >r abs -rot
     s>d r> xor r> swap >r >r dabs rot tuck um* 2swap um*
-    swap >r 0 d+ r> -rot r@ um/mod -rot r> um/mod nip swap
-    r> IF dnegate THEN ;
+    swap >r 0 d+ r> -rot r@ um/mod -rot r> um/mod
+    [ 1 -3 mod 0< ] [if]
+        -rot r> IF IF 1. d+ THEN dnegate ELSE drop THEN
+    [else]
+        nip swap r> IF dnegate THEN
+    [then] ;
 
 \ CASE OF ENDOF ENDCASE                                 17may93jaw
 
@@ -58,11 +63,12 @@ decimal
 0 CONSTANT case ( compilation  -- case-sys ; run-time  -- ) \ core-ext
     immediate
 
+: ?of ( compilation  -- of-sys ; run-time  f -- ) \ gforth
+    1+ >r POSTPONE if r> ; immediate
+
 : of ( compilation  -- of-sys ; run-time x1 x2 -- |x1 ) \ core-ext
     \ !! the implementation does not match the stack effect
-    1+ >r
-    postpone over postpone = postpone if postpone drop
-    r> ; immediate
+    postpone over postpone = postpone ?of postpone drop ; immediate
 
 : endof ( compilation case-sys1 of-sys -- case-sys2 ; run-time  -- ) \ core-ext end-of
     >r postpone else r> ; immediate
@@ -92,8 +98,8 @@ decimal
 
 \ CONVERT                                               17may93jaw
 
-: convert ( ud1 c-addr1 -- ud2 c-addr2 ) \ core-ext
-    \G OBSOLESCENT: superseded by @code{>number}.
+: convert ( ud1 c-addr1 -- ud2 c-addr2 ) \ core-ext-obsolescent
+    \G Obsolescent: superseded by @code{>number}.
     char+ true >number drop ;
 
 \ ERASE                                                 17may93jaw
@@ -118,7 +124,7 @@ decimal
     begin
 	dup r@ >=
     while
-	over 2r@ swap -text 0= if
+	2dup 2r@ string-prefix? if
 	    2swap 2drop 2r> 2drop true exit
 	endif
 	1 /string
@@ -182,11 +188,11 @@ decimal
 
 \ EXPECT SPAN                                           17may93jaw
 
-variable span ( -- c-addr ) \ core-ext
+variable span ( -- c-addr ) \ core-ext-obsolescent
 \G @code{Variable} -- @i{c-addr} is the address of a cell that stores the
 \G length of the last string received by @code{expect}. OBSOLESCENT.
 
-: expect ( c-addr +n -- ) \ core-ext
+: expect ( c-addr +n -- ) \ core-ext-obsolescent
     \G Receive a string of at most @i{+n} characters, and store it
     \G in memory starting at @i{c-addr}. The string is
     \G displayed. Input terminates when the <return> key is pressed or
@@ -194,9 +200,10 @@ variable span ( -- c-addr ) \ core-ext
     \G editing capabilites are available. The length of the string is
     \G stored in @code{span}; it does not include the <return>
     \G character. OBSOLESCENT: superceeded by @code{accept}.
+    everyline
     0 rot over
     BEGIN ( maxlen span c-addr pos1 )
-	key decode ( maxlen span c-addr pos2 flag )
+	xkey decode ( maxlen span c-addr pos2 flag )
 	>r 2over = r> or
     UNTIL
     2 pick swap /string type
@@ -208,15 +215,7 @@ variable span ( -- c-addr ) \ core-ext
 \ defined afterwards) when executing the mark.
 
 : included-files-mark ( -- u )
-    included-files 2@ nip
-    blk @ 0=
-    if \ not input from blocks
-	source-id 1 -1 within
-	if \ input from file
-	    1- \ do not include the last file (hopefully this is the
-	       \ currently included file)
-	then
-    then ;  
+    included-files @ ;
 
 \ hmm, most of the saving appears to be pretty unnecessary: we could
 \ derive the wordlists and the words that have to be kept from the
@@ -242,7 +241,7 @@ variable span ( -- c-addr ) \ core-ext
 
 : marker! ( mark -- )
     \ reset included files count; resize will happen on next add-included-file
-    included-files 2@ drop over @ included-files 2! cell+
+    included-files @ over @ min included-files ! cell+
     \ rest of marker!
     dup @ swap cell+ ( here rest-of-marker )
     dup @ voclink ! cell+
@@ -266,7 +265,7 @@ variable span ( -- c-addr ) \ core-ext
     drop
     \ restore udp and dp
 [IFDEF] forget-dyncode
-    dup cell+ @ forget-dyncode 0= abort" gforth bug"
+    dup cell+ @ forget-dyncode drop
 [THEN]
     @ udp !  dp !
     \ clean up vocabulary stack