Brainfuck Interpreter

[frank26080115]

I made a simple Brainfuck interpreter, this is a step towards a microcontroller assembly/machine code simulation.
Learn about Brainfuck and its syntax here:
http://en.wikipedia.org/wiki/Brainfuck

Note that my version allows variables and pointers to decrement from 0 to 255 and increment from 255 to 0

Turing:

setscreen ("graphics:1000,600;position:center,center;offscreenonly;title:Brainfuck") %;nobuttonbar") const maxAddress := 255 var address : array 0 .. maxAddress of int var _pointer : int var code : string := "" var ch : string (1) var loopCounter, location : int var finished, _return : boolean var chars : array char of boolean fcn getInput (fieldName, starting : string, maxLength : int, interger : boolean) : string     var character : string (1)     var cursorLoc : int := 0     var output : string := starting     var legalString : string := " ~!@#$%\^&*()_+`1234567890-=qwertyuiop[]\\asdfghjkl;'zxcvbnm,./QWERTYUIOP{}|ASDFGHJKL:\"ZXCVBNM<>?" %"<>+-,.[]"     var exit123 : boolean := false     if interger then         legalString := "1234567890"     end if     loop         if hasch then             getch (character)             if character = KEY_BACKSPACE then                 if length (output) > 0 and cursorLoc > 0 then                     output := output (1 .. cursorLoc - 1) + output (cursorLoc + 1 .. *)                     cursorLoc -= 1                 end if             elsif character = KEY_DELETE then                 if cursorLoc < length (output) then                     output := output (1 .. cursorLoc) + output (cursorLoc + 2 .. *)                 end if             elsif character = KEY_ENTER then                 cursorLoc := 0                 exit123 := true             elsif character = KEY_RIGHT_ARROW then                 if cursorLoc < length (output) then                     cursorLoc += 1                 end if             elsif character = KEY_LEFT_ARROW then                 if cursorLoc > 0 then                     cursorLoc -= 1                 end if             elsif character = KEY_HOME then                 cursorLoc := 0             elsif character = KEY_END then                 cursorLoc := length (output)             else                 if length (output) < maxLength and index (legalString, character) not= 0 then                     output := output (1 .. cursorLoc) + character + output (cursorLoc + 1 .. *)                     cursorLoc += 1                 end if             end if         end if         Text.Locate (Text.WhatRow, 1)         for i : 1 .. length (fieldName) + length (output) + 2             put " " ..         end for         Text.Locate (Text.WhatRow, 1)         put fieldName ..         for i : 1 .. cursorLoc - 1             put output (i) ..         end for         if (Time.Elapsed div 500) mod 2 = 1 and exit123 = false then             if cursorLoc not= 0 then                 put output (cursorLoc) ..             end if             if cursorLoc = length (output) then                 put "|" ..             else                 put "<" ..             end if             for i : cursorLoc + 2 .. length (output)                 if i not= 0 then                     put output (i) ..                 end if             end for         else             if cursorLoc not= 0 then                 put output (cursorLoc) ..             end if             for i : cursorLoc + 1 .. length (output)                 if i not= 0 then                     put output (i) ..                 end if             end for         end if         put " " ..         View.Update         Time.DelaySinceLast (100)         exit when exit123     end loop     if interger and strintok (output) = false then         output := "0"     end if     put ""     result output end getInput proc executeCommand (toExe : string)     if toExe = "<" then         if _pointer = 0 then             _pointer := maxAddress         else             _pointer -= 1         end if     elsif toExe = ">" then         if _pointer = maxAddress then             _pointer := 0         else             _pointer += 1         end if     elsif toExe = "+" then         if address (_pointer) = 255 then             address (_pointer) := 0         else             address (_pointer) += 1         end if     elsif toExe = "-" then         if address (_pointer) = 0 then             address (_pointer) := 255         else             address (_pointer) -= 1         end if     elsif toExe = "," then         loop             Time.DelaySinceLast (100)             exit when hasch         end loop         getch (ch)         if ord (ch) > 126 then             address (_pointer) := 126         elsif ord (ch) = 10 then             address (_pointer) := 10         elsif ord (ch) < 32 then             address (_pointer) := 32         else             address (_pointer) := ord (ch)         end if     elsif toExe = "." then         %put "Byte: ", address (_pointer), "  " ..         if address (_pointer) >= 32 and address (_pointer) <= 126 or address (_pointer) = 10 then             put chr (address (_pointer)) .. %put "Char: ", chr (address (_pointer))         else             %put ""         end if         View.Update     end if end executeCommand loop     put "Welcome to the Brainfuck Interpreter by Frank26080115"     View.Update     code := getInput ("Input Code: ", code, 250, false) + " "     put "Begin Execution (EXE to stop)"     put "Output:"     put "-----------------------------"     put ""     View.Update     _pointer := 0     for i : 0 .. 255         address (i) := 0     end for     loopCounter := 0     location := 1     finished := false     loop         for i : location .. length (code)             _return := false             executeCommand (code (i)) %executes simple code                         %these handle loops, loopCounter is used to             %deal with nested loops             if code (i) = "[" then                 if address (_pointer) = 0 then                     for j : i + 1 .. length (code)                         if code (j) = "[" then                             loopCounter += 1                         elsif code (j) = "]" then                             if loopCounter = 0 then                                 exit                             else                                 loopCounter -= 1                             end if                         end if                     end for                 end if             elsif code (i) = "]" then                 if address (_pointer) > 0 then                     for decreasing j : i - 1 .. 1                         if code (j) = "[" then                             if loopCounter = 0 then                                 location := j                                 _return := true                                 exit                             else                                 loopCounter -= 1                             end if                         end if                     end for                 end if             end if             if i = length (code) then                 finished := true             end if             if _return then                 _return := false                 exit             end if             Input.KeyDown (chars)             if chars (KEY_ESC) then                 finished := true                 exit             end if         end for         exit when finished     end loop     put ""     put ""     put "-----------------------------"     put "Finished Execution" ..     if chars (KEY_ESC) then         put " (User Interrupted)"     end if     put "\n" end loop

for an example, "+[,.]" will become something like notepad, "+[.+]" will show all printable characters and then exit the loop, "+[.+.+]" will loop forever while printing all printable characters, have fun[/syntax]

[CodeMonkey2000]

0_o Holy crap. This is amazing. But I still don't plan on ever using BF.

[Ultrahex]

Overall the program is excellent.

You should make it more "clean", so its not as over cumbersomely (hehe, no clue if that is correct english). For Example:

Quote:

Welcome to the Brainfuck Interpreter by Frank26080115

Input Below:

:: <>++++++[<-------->-],[<+>-]<.
::: 2
::: 3
5

:: ....(other examples)
Hello World

::

note that i may be the only one annoyed because I like to have clean looking interfaces, and most people that use interpreters understand that it is an input field etc... Just Some Ideas

[Tony]

this is quite cool +bits

[shakin cookie]

I do not understand how this works...

[StealthArcher]

You have to know what Brain**** is first really.

Then you will be amazed.

And I am amazed. +bits