# New Ticket Created by Stepan Roh
# Please include the string: [perl #32112]
# in the subject line of all future correspondence about this issue.
# <URL: http://rt.perl.org:80/rt3/Ticket/Display.html?id=32112 >
While playing with Parrot I found a few bugs and problems in Befunge
interpreter. Although it is not important part of Parrot I tried to fix
them. All changes are in attached patch created with cvs diff -u against
CVS HEAD 2004/10/23 and one new file.
Changes:
- Befunge-97 directives (lines starting with =) are ignored
- stdout buffering is disabled
- fixed bug in integer input (instead of read integer, length of it's
string representation was returned)
- fixed bug in integer input (only integers with one digit were
allowed which was fixed by using readline instead of read)
- when outputing integer, output one space as well to conform with specs
I tested all Befunge scripts I have and there is one which does not work
as expected. I attached it as pascserp.bef, it is also mentioned in
README.
Hope I did everything right.
Have a nice day.
Stepan Roh
Index: languages/befunge/README
===================================================================
RCS file: /cvs/public/parrot/languages/befunge/README,v
retrieving revision 1.9
diff -u -r1.9 README
--- languages/befunge/README 6 Feb 2004 14:23:09 -0000 1.9
+++ languages/befunge/README 23 Oct 2004 15:20:50 -0000
@@ -35,12 +35,14 @@
developement
test.bef a befunge script that test almost all the
instructions (and is even self-modifying!)
+ pascserp.bef a befunge script generating variant of Sierpinsky
+ triangle (by Chris Pressey)
BUGS
----
-* The "input char" and "input int" instructions are a bit broken since
- Parrot does not handle I/O very well...
+* pascserp.bef output is not correct (right bottom part of image is just
+noise)
TODO
Index: languages/befunge/befunge.pasm
===================================================================
RCS file: /cvs/public/parrot/languages/befunge/befunge.pasm,v
retrieving revision 1.5
diff -u -r1.5 befunge.pasm
--- languages/befunge/befunge.pasm 30 Aug 2003 10:01:11 -0000 1.5
+++ languages/befunge/befunge.pasm 23 Oct 2004 15:20:51 -0000
@@ -8,6 +8,8 @@
.include "stack.pasm"
MAIN:
+ getstdout P10
+ pioctl I10, P10, 3, 0 # disable buffering on stdout
set I0, 0
set I5, 0 # debug mode
ARGV_NEXT:
Index: languages/befunge/io.pasm
===================================================================
RCS file: /cvs/public/parrot/languages/befunge/io.pasm,v
retrieving revision 1.4
diff -u -r1.4 io.pasm
--- languages/befunge/io.pasm 21 Dec 2002 16:56:09 -0000 1.4
+++ languages/befunge/io.pasm 23 Oct 2004 15:20:51 -0000
@@ -22,7 +22,8 @@
restore S2
length I10, S2
gt I10, 0, IO_INPUT_INT_PARSE_INPUT
- read S2, 1
+ getstdin P15
+ readline S2, P15
length I10, S2
IO_INPUT_INT_PARSE_INPUT:
set I11, 0
@@ -38,7 +39,7 @@
set I11, 0
IO_INPUT_INT_NAN:
substr S2, S2, I11, I10
- push P2, I10
+ push P2, S10
pops
popi
branch MOVE_PC
@@ -55,7 +56,8 @@
restore S2
length I10, S2
gt I10, 0, IO_INPUT_CHAR_SUBSTR
- read S2, 1
+ getstdin P15
+ readline S2, P15
IO_INPUT_CHAR_SUBSTR:
substr S10, S2, 0, 1
length I10, S2
@@ -80,6 +82,7 @@
pop I10, P2
IO_OUTPUT_INT_POP_1:
print I10
+ print " "
popi
branch MOVE_PC
Index: languages/befunge/load.pasm
===================================================================
RCS file: /cvs/public/parrot/languages/befunge/load.pasm,v
retrieving revision 1.3
diff -u -r1.3 load.pasm
--- languages/befunge/load.pasm 21 Dec 2002 16:56:09 -0000 1.3
+++ languages/befunge/load.pasm 23 Oct 2004 15:20:51 -0000
@@ -44,7 +44,10 @@
branch LOAD_FILL_LINE
LOAD_TRUNCATE_LINE:
set P2, 80 # Truncate the line.
+ set I11, P2[0] # Skip lines with leading "=" (Befunge-97 directive)
+ eq I11, 0x3d, LOAD_SKIP_DIRECTIVE
push P1, P2 # Store the line.
+LOAD_SKIP_DIRECTIVE:
new P2, .PerlArray # Create a new line.
branch LOAD_PARSE_BUFFER
58*00p010p>58*00g-|>0g#<1-10gg00g10v
v98p00:+1g00< v67<> >1 v+g-1g<
>*7+-! #v_v>^^< |%2pg0 1g00:<
v p00*58< ^,<^48<>10g!|@
>52*,10g1+ :1 0p83 *- ! |
v <
