1 files changed, 40 insertions, 24 deletions

diff --git a/main/main.go b/main/main.go
index b7ef568..3a864ad 100644
--- a/main/main.go
+++ b/main/main.go
@@ -1,6 +1,7 @@
 package main
 
 import (
+	"io"
 	"os"
 	"bufio"
 	"main/walk"
@@ -15,32 +16,19 @@ type ProgramState struct {
 	pc int
 }
 
-func main() {
-	quiet := false
-	var input string
-	hasInput := false
-	
-	for i := 1; i < len(os.Args); i += 1 {
-		switch os.Args[i] {
-			case "-n":
-				quiet = true
-				continue
-		}
-		if i < len(os.Args) - 1 {
-			panic("Unexpected arguments after program")
-		}
-		input = os.Args[i]
-		hasInput = true
-	}
-	if !hasInput {
-		panic("Missing program")
-	}
+type config struct {
+	quiet bool
+	program string
+	in io.Reader
+	out io.Writer
+}
 
-	tokens := Lex(input)
+func run(config config) {
+	tokens := Lex(config.program)
 	program := Parse(tokens)
 
-	stdin := bufio.NewReader(os.Stdin)
-	stdout := bufio.NewWriter(os.Stdout)
+	stdin := bufio.NewReader(config.in)
+	stdout := bufio.NewWriter(config.out)
 
 	state := ProgramState {
 		in: json.NewJSONReader(stdin),
@@ -58,7 +46,7 @@ func main() {
 		for state.pc < len(state.program) {
 			state.program[state.pc].exec(&state)
 		}
-		if !quiet {
+		if !config.quiet {
 			for _, value := range state.value {
 				err := state.out.Write(value)
 				if err != nil {
@@ -71,3 +59,31 @@ func main() {
 	state.in.AssertDone()
 	state.out.AssertDone()
 }
+
+func main() {
+	config := config {
+		quiet: false,
+		in: os.Stdin,
+		out: os.Stdout,
+	}
+	hasInput := false
+	
+	for i := 1; i < len(os.Args); i += 1 {
+		switch os.Args[i] {
+			case "-n":
+				config.quiet = true
+				continue
+		}
+		if i < len(os.Args) - 1 {
+			panic("Unexpected arguments after program")
+		}
+		config.program = os.Args[i]
+		hasInput = true
+	}
+	if !hasInput {
+		panic("Missing program")
+	}
+
+	run(config)
+
+}