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brainfuck: some cleanup and make the ebnf simpler.

db4
John Benediktsson 2011-08-26 18:42:17 -07:00
parent dd280eae9a
commit 02181a5d50
1 changed files with 16 additions and 16 deletions
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14
extra/brainfuck/brainfuck.factor
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@ -1,8 +1,8 @@
! Copyright (C) 2009 John Benediktsson
! See http://factorcode.org/license.txt for BSD license
USING: accessors assocs fry io io.streams.string kernel macros math
peg.ebnf prettyprint quotations sequences strings ;
USING: accessors assocs fry io io.streams.string kernel macros
math peg.ebnf prettyprint sequences strings ;
IN: brainfuck
@ -50,10 +50,10 @@ TUPLE: brainfuck pointer memory ;
EBNF: parse-brainfuck
inc-ptr = (">")+ => [[ length 1quotation [ (>) ] append ]]
dec-ptr = ("<")+ => [[ length 1quotation [ (<) ] append ]]
inc-mem = ("+")+ => [[ length 1quotation [ (+) ] append ]]
dec-mem = ("-")+ => [[ length 1quotation [ (-) ] append ]]
inc-ptr = (">")+ => [[ length [ (>) ] curry ]]
dec-ptr = ("<")+ => [[ length [ (<) ] curry ]]
inc-mem = ("+")+ => [[ length [ (+) ] curry ]]
dec-mem = ("-")+ => [[ length [ (-) ] curry ]]
output = "." => [[ [ (.) ] ]]
input = "," => [[ [ (,) ] ]]
debug = "#" => [[ [ (#) ] ]]
@ -61,7 +61,7 @@ space = (" "|"\t"|"\r\n"|"\n")+ => [[ [ ] ]]
unknown = (.) => [[ "Invalid input" throw ]]
ops = inc-ptr|dec-ptr|inc-mem|dec-mem|output|input|debug|space
loop = "[" {loop|ops}+ "]" => [[ second compose-all 1quotation [ [ (?) ] ] prepend [ while ] append ]]
loop = "[" {loop|ops}+ "]" => [[ second compose-all [ while ] curry [ (?) ] prefix ]]
code = (loop|ops|unknown)* => [[ compose-all ]]