Execute Brain****/F Sharp
Execute Brain****/F Sharp is an implementation of Brainf***.
Other implementations of Brainf***.
Execute Brain****/F Sharp is part of RCBF. You may find other members of RCBF at Category:RCBF.
<lang fsharp>open System
open System.Collections.Generic
let Rcbf (pgmStr : string) (input : int array) =
let pgm = Seq.toArray pgmStr // Turn program into an array let ptr = ref 0 // Pointer into input let ip = ref 0 // Instruction Pointer
let InputNumber() = let mutable fValid = false let mutable num = 0 printfn "Enter a valid number" fValid <- System.Int32.TryParse(Console.ReadLine(), &num); while not fValid do printfn "Invalid input. Please enter a valid number" fValid <- System.Int32.TryParse(Console.ReadLine(), &num); num
let AdvanceIp() = ip := !ip + 1 // Advance IP let RetreatIp() = ip := !ip - 1 // Decrement IP
let SkipBrackets fForward = if input.[!ptr] <> 0 then // If we have a 0 input AdvanceIp() // Then just advance to next instruction else // otherwise let fnMove = if fForward then AdvanceIp else RetreatIp // get the appropriate function to move forward or backward let mutable cBrackets = 1 // Count of brackets we've seen while cBrackets > 0 do // While we have unmatched brackets fnMove() // move to the next character if !ip >= 0 && !ip < pgm.Length then // and if we're still within range match pgm.[!ip] with // look at the character | '[' -> cBrackets <- cBrackets + 1 // If it's a '[' then count up brackets | ']' -> cBrackets <- cBrackets - 1 // If it's a ']' then count down brackets | _ -> ignore(0) // Ignore anything else AdvanceIp() // When we're on the matching bracket, skip to the next instruction
let interpretCmd() = match pgm.[!ip] with | '>' -> ptr := !ptr + 1; AdvanceIp() | '<' -> ptr := !ptr - 1; AdvanceIp() | '+' -> input.[!ptr] <- input.[!ptr] + 1; AdvanceIp() | '-' -> input.[!ptr] <- input.[!ptr] - 1; AdvanceIp() | '.' -> printf "%c" (char input.[!ptr]); AdvanceIp() | ',' -> input.[!ptr] <- InputNumber(); AdvanceIp() | '[' -> SkipBrackets true | ']' -> SkipBrackets false | _ -> ignore(0)
while !ip >= 0 && !ip < pgm.Length do interpretCmd()</lang>
Hello world in RCBF (stolen from the Wiki site): <lang fsharp>let pgmHelloWorld = "++++++++++[>+++++++>++++++++++>+++>+<<<<-]>++.>+.+++++++..+++.>++.<<+++++++++++++++.>.+++.------.--------.>+.>." let tape = Array.create 5 0 Rcbf pgmHelloWorld tape</lang>