From b062a9092ad711968b3ee4ce0848f2eaa4fd671c Mon Sep 17 00:00:00 2001
From: Virgil Dupras <hsoft@hardcoded.net>
Date: Sat, 18 Apr 2020 09:13:23 -0400
Subject: [PATCH] parse: use "0<" instead of "0 <"

As I wrote in my "Clarify signed-ness" commit, "0 <" is broken.

Also, made this unit a bit more compact. The RC2014 stage1 can
really use some breathing room...
---
 blk/018             |   2 +-
 emul/forth/z80c.bin | Bin 2172 -> 2186 bytes
 forth/cmp.fs        |   3 +--
 forth/fmt.fs        |   2 +-
 forth/icore.fs      |   3 ++-
 forth/parse.fs      |  36 +++++++++++++++++-------------------
 6 files changed, 22 insertions(+), 24 deletions(-)

diff --git a/blk/018 b/blk/018
index ea7977c..93ae784 100644
--- a/blk/018
+++ b/blk/018
@@ -5,7 +5,7 @@ unsigned. For convenience, decimal parsing and formatting
 support the "-" prefix, but under the hood, it's all unsigned.
 
 This leads to some oddities. For example, "-1 0 <" is false.
-To compare whether something is negative, use the "<0" word
+To compare whether something is negative, use the "0<" word
 which is the equivalent to "0x7fff >".
 
 
diff --git a/emul/forth/z80c.bin b/emul/forth/z80c.bin
index c13545b3e130ec6bee961d10b9cfea535772d9eb..bf11c6b5ade3c82d0c379fa0f80453d2cd8f0ae6 100644
GIT binary patch
delta 285
zcmew(&?UH`hLzjEhMR$jPl4foeevW<)>6UetnMs*jEkA}F*-50v+QG>Jo!JXG?0{L
zlVN;5*@7*THH>W`<BZA6*yOd>v0Y&N!<5Sc7GX<g`1Jn=qXGjT!&(+6hG6G_NOcAl
zzJ-iB%nKRoCx2j5@%+a2h=qr_hGik+BbGlv8x}Kx_?)af%!`@Q+3LZvoUDJCoES7x
z^Gb>;H7yv}`OdIOvpX?(`h~a#1q8W<2rzK+otYfVzFasHDD2}I;uiz7MS($qA)PIK
zvN(s5b2{66=1oA?Tk$b4@`bU398}MChE0++ok5IYA)_HjIs*qo17k1)3s6fi0~f<3
Vpd%U>WjTTwZvA&+h&N$i1OURDNLv5^

delta 258
zcmeAY{3EcThIMimYmwkhR(F;@#>Gtg7@Zj0S@touPUdBk29la=GK@DTyRl^&dax~I
z>|(2DN@rkUaAMfR7|ihQzY{~ae~^nb0}G!510Ta$mIZ7V82>QkvVhf2e!wQnSUC9~
zn~MAkwnr>H%rz_v86UCy0ot*c3B>1Q<zZgT6v<XN*^ymLWFH$ZyAy+_Ux;f^K#*&Q
z00SrAzRB6_%Y~zX!aklMelcKc6c{4eA}6bIC^<*6&1c>ObgmU210$aYJIDovZ2Q<G
sS<@NB7#1=rbEGqHFf;(&$pX|8%)rHP320{nBR@wl!!4l8<4qVC0XmmH`2YX_

diff --git a/forth/cmp.fs b/forth/cmp.fs
index 866bae5..eecad15 100644
--- a/forth/cmp.fs
+++ b/forth/cmp.fs
@@ -2,8 +2,7 @@
 
 : >= < NOT ;
 : <= > NOT ;
-: <0 32767 > ;
-: >=0 <0 NOT ;
+: 0>= 0< NOT ;
 
 ( n1 -- n1 true )
 : <>{ 1 ;
diff --git a/forth/fmt.fs b/forth/fmt.fs
index b5b1b6d..ad42f0c 100644
--- a/forth/fmt.fs
+++ b/forth/fmt.fs
@@ -12,7 +12,7 @@
 
 : .               ( n -- )
     ( handle negative )
-    DUP <0 IF '-' EMIT -1 * THEN
+    DUP 0< IF '-' EMIT -1 * THEN
     _
     BEGIN
     DUP '9' > IF DROP EXIT THEN  ( stop indicator, we're done )
diff --git a/forth/icore.fs b/forth/icore.fs
index 9cb00bc..e898ba8 100644
--- a/forth/icore.fs
+++ b/forth/icore.fs
@@ -51,6 +51,7 @@
 : = CMP NOT ;
 : < CMP -1 = ;
 : > CMP 1 = ;
+: 0< 32767 > ;
 
 ( r c -- r f )
 ( Parse digit c and accumulate into result r.
@@ -61,7 +62,7 @@
     ( parse char )
     '0' -
     ( if bad, return "r -1" )
-    DUP 0 < IF DROP -1 EXIT THEN   ( bad )
+    DUP 0< IF DROP -1 EXIT THEN    ( bad )
     DUP 9 > IF DROP -1 EXIT THEN   ( bad )
     ( good, add to running result )
     SWAP 10 * +                    ( r*10+n )
diff --git a/forth/parse.fs b/forth/parse.fs
index fa1af00..93a6393 100644
--- a/forth/parse.fs
+++ b/forth/parse.fs
@@ -11,14 +11,14 @@
 ;
 
 ( returns negative value on error )
-: hexdig            ( c -- n )
+: _            ( c -- n )
     ( '0' is ASCII 48 )
     48 -
-    DUP 0 < IF EXIT THEN                ( bad )
+    DUP 0< IF EXIT THEN                 ( bad )
     DUP 10 < IF EXIT THEN               ( good )
     ( 'a' is ASCII 97. 59 = 97 - 48 )
     49 -
-    DUP 0 < IF EXIT THEN                ( bad )
+    DUP 0< IF EXIT THEN                 ( bad )
     DUP 6 < IF 10 + EXIT THEN           ( good )
     ( bad )
     255 -
@@ -31,24 +31,23 @@
     2+
     ( validate slen )
     DUP SLEN                            ( a l )
-    DUP 0 = IF DROP 0 EXIT THEN         ( a 0 )
+    DUP NOT IF DROP 0 EXIT THEN         ( a 0 )
     4 > IF DROP 0 EXIT THEN             ( a 0 )
-    0 ( a r )
+    0  ( a r )
     BEGIN
-    OVER C@
-    DUP 0 = IF DROP SWAP DROP 1 EXIT THEN ( r, 1 )
-    hexdig                              ( a r n )
-    DUP 0 < IF DROP DROP 1 EXIT THEN    ( a 0 )
-    SWAP 16 * +                         ( a r*16+n )
-    SWAP 1+ SWAP                        ( a+1 r )
+    SWAP C@+                            ( r a+1 c )
+    DUP NOT IF 2DROP 1 EXIT THEN        ( r, 1 )
+    _                                   ( r a n )
+    DUP 0< IF ROT 2DROP 0 EXIT THEN     ( a 0 )
+    ROT 16 * +                          ( a r*16+n )
     AGAIN
 ;
 
 ( returns negative value on error )
-: bindig            ( c -- n )
+: _            ( c -- n )
     ( '0' is ASCII 48 )
     48 -
-    DUP 0 < IF EXIT THEN                ( bad )
+    DUP 0< IF EXIT THEN                 ( bad )
     DUP 2 < IF EXIT THEN                ( good )
     ( bad )
     255 -
@@ -65,12 +64,11 @@
     16 > IF DROP 0 EXIT THEN            ( a 0 )
     0 ( a r )
     BEGIN
-    OVER C@
-    DUP 0 = IF DROP SWAP DROP 1 EXIT THEN ( r, 1 )
-    bindig                              ( a r n )
-    DUP 0 < IF DROP DROP 1 EXIT THEN    ( a 0 )
-    SWAP 2 * +                          ( a r*2+n )
-    SWAP 1+ SWAP                        ( a+1 r )
+    SWAP C@+                               ( r a+1 c )
+    DUP NOT IF 2DROP 1 EXIT THEN           ( r 1 )
+    _                                      ( r a n )
+    DUP 0< IF ROT 2DROP 0 EXIT THEN        ( a 0 )
+    ROT 2 * +                              ( a r*2+n )
     AGAIN
 ;