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db4
John Benediktsson 2009-06-07 15:21:39 -07:00
parent 2a5db1abd9
commit 6b86f059e7
1 changed files with 13 additions and 13 deletions
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26
extra/brainfuck/brainfuck.factor
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@ -19,11 +19,11 @@ TUPLE: brainfuck pointer memory ;
: set-memory ( brainfuck value -- brainfuck )
over [ pointer>> ] [ memory>> ] bi set-at ;
: (+) ( brainfuck -- brainfuck )
get-memory 1 + 255 bitand set-memory ;
: (+) ( brainfuck n -- brainfuck )
[ get-memory ] dip + 255 bitand set-memory ;
: (-) ( brainfuck -- brainfuck )
get-memory 1 - 255 bitand set-memory ;
: (-) ( brainfuck n -- brainfuck )
[ get-memory ] dip - 255 bitand set-memory ;
: (?) ( brainfuck -- brainfuck t/f )
get-memory 0 = not ;
@ -34,24 +34,24 @@ TUPLE: brainfuck pointer memory ;
: (,) ( brainfuck -- brainfuck )
read1 set-memory ;
: (>) ( brainfuck -- brainfuck )
[ 1 + ] change-pointer ;
: (>) ( brainfuck n -- brainfuck )
[ dup pointer>> ] dip + >>pointer ;
: (<) ( brainfuck -- brainfuck )
[ 1 - ] change-pointer ;
: (<) ( brainfuck n -- brainfuck )
[ dup pointer>> ] dip - >>pointer ;
: compose-all ( seq -- quot )
[ ] [ compose ] reduce ;
EBNF: parse-brainfuck
inc-ptr = ">" => [[ [ (>) ] ]]
dec-ptr = "<" => [[ [ (<) ] ]]
inc-mem = "+" => [[ [ (+) ] ]]
dec-mem = "-" => [[ [ (-) ] ]]
inc-ptr = (">")+ => [[ length 1quotation [ (>) ] append ]]
dec-ptr = ("<")+ => [[ length 1quotation [ (<) ] append ]]
inc-mem = ("+")+ => [[ length 1quotation [ (+) ] append ]]
dec-mem = ("-")+ => [[ length 1quotation [ (-) ] append ]]
output = "." => [[ [ (.) ] ]]
input = "," => [[ [ (,) ] ]]
space = (" "|"\t"|"\r\n"|"\n") => [[ [ ] ]]
space = (" "|"\t"|"\r\n"|"\n")+ => [[ [ ] ]]
unknown = (.) => [[ "Invalid input" throw ]]
ops = inc-ptr | dec-ptr | inc-mem | dec-mem | output | input | space