Added functional programming version of go bf2

brainfuck2/bf_func.go

@@ -0,0 +1,131 @@
+package main
+
+import "fmt"
+import "os"
+import "io/ioutil"
+
+const (
+	INC = iota
+	MOVE
+	PRINT
+	LOOP
+)
+
+type Op func(*Tape)
+
+type StringIterator struct {
+	Text []byte
+	Pos  int
+}
+
+func NewStringIterator(s string) *StringIterator {
+	si := &StringIterator{Text: []byte(s), Pos: 0}
+	return si
+}
+
+func (si *StringIterator) Next() byte {
+	if si.Pos < len(si.Text) {
+		res := si.Text[si.Pos]
+		si.Pos++
+		return res
+	} else {
+		return byte(0)
+	}
+}
+
+type Tape struct {
+	tape []int
+	pos  int
+}
+
+func NewTape() *Tape {
+	t := &Tape{pos: 0}
+	t.tape = make([]int, 1)
+	t.Move(1)
+	return t
+}
+
+func (t *Tape) Inc(x int) {
+	t.tape[t.pos] += x
+}
+
+func (t *Tape) Move(x int) {
+	t.pos += x
+	for t.pos >= len(t.tape) {
+		t.tape = append(t.tape, 0)
+	}
+}
+
+func (t *Tape) Get() int {
+	return t.tape[t.pos]
+}
+
+type Program struct {
+	Ops []Op
+}
+
+func NewProgram(code string) *Program {
+	return &Program{Ops: parse(NewStringIterator(code))}
+}
+
+func (p *Program) Run() {
+	_run(p.Ops, NewTape())
+}
+
+func parse(si *StringIterator) []Op {
+	var res []Op
+	var do Op
+	for true {
+		c := si.Next()
+		switch c {
+		case '+':
+			do = func(t *Tape) {
+				t.Inc(1)
+			}
+		case '-':
+			do = func(t *Tape) {
+				t.Inc(-1)
+			}
+		case '>':
+			do = func(t *Tape) {
+				t.Move(1)
+			}
+		case '<':
+			do = func(t *Tape) {
+				t.Move(-1)
+			}
+		case '.':
+			do = func(t *Tape) {
+				fmt.Printf("%c", t.tape[t.pos])
+			}
+		case '[':
+			program := parse(si)
+			do = func(t *Tape) {
+				for t.Get() != 0 {
+					// Call run as long as val != 0
+					_run(program, t)
+				}
+			}
+		case ']', 0:
+			return res
+		default:
+			do = func(t *Tape) {} // no-op
+		}
+		res = append(res, do)
+	}
+	return res
+}
+
+func _run(program []Op, tape *Tape) {
+	for _, op := range program {
+		op(tape)
+	}
+}
+
+func main() {
+	Code, err := ioutil.ReadFile(os.Args[1])
+	if err != nil {
+		panic(fmt.Sprintf("%v", err))
+	}
+	NewProgram(string(Code)).Run()
+}

brainfuck2/build.sh

@@ -7,6 +7,7 @@ dotnet restore && dotnet build -c Release
 javac bf.java
 kotlinc bf2.kt -include-runtime -d bf2-kt.jar
 go build -o bin_go bf.go
+go build -o bin_go_func bf_func.go
 gccgo -O3 -g -o bin_go_gccgo bf.go
 dmd -ofbin_d -O -release -inline bf.d
 gdc -o bin_d_gdc -O3 -frelease -finline bf.d

brainfuck2/run.sh

@@ -20,6 +20,8 @@ echo Javascript Node
 ../xtime.rb node bf.js bench.b
 echo Go
 ../xtime.rb ./bin_go bench.b
+echo Functional Go
+../xtime.rb ./bin_go_func bench.b
 echo Go Gcc
 ../xtime.rb ./bin_go_gccgo bench.b
 echo D Dmd

brainfuck2/run2.sh

@@ -22,6 +22,8 @@ echo Kotlin
 ../xtime.rb java -jar bf2-kt.jar mandel.b > /dev/null
 echo Go
 ../xtime.rb ./bin_go mandel.b > /dev/null
+echo Functional Go
+../xtime.rb ./bin_go_func mandel.b > /dev/null
 echo Go Gcc
 ../xtime.rb ./bin_go_gccgo mandel.b > /dev/null
 echo Javascript Node