From 36f04713bde2d34185fb3cc581ee7f037f4c9fb3 Mon Sep 17 00:00:00 2001
From: Chuck Smith <smitty7887@gmail.com>
Date: Thu, 14 Mar 2024 20:11:29 -0400
Subject: [PATCH] fibonacci

---
 main.go       | 76 ++++++++++++++++++++++++++++++++++++++++++++-------
 vm/vm_test.go | 24 ++++++++++++++++
 2 files changed, 90 insertions(+), 10 deletions(-)

diff --git a/main.go b/main.go
index 830498c..86255a6 100644
--- a/main.go
+++ b/main.go
@@ -1,19 +1,75 @@
 package main
 
 import (
+	"flag"
 	"fmt"
-	"monkey/repl"
-	"os"
-	user2 "os/user"
+	"time"
+
+	"monkey/compiler"
+	"monkey/evaluator"
+	"monkey/lexer"
+	"monkey/object"
+	"monkey/parser"
+	"monkey/vm"
 )
 
-func main() {
-	user, err := user2.Current()
+var engine = flag.String("engine", "vm", "use 'vm' or 'eval'")
 
-	if err != nil {
-		panic(err)
+var input = `
+let fibonacci = fn(x) {
+  if (x == 0) {
+    0
+  } else {
+    if (x == 1) {
+      return 1;
+    } else {
+      fibonacci(x - 1) + fibonacci(x - 2);
+    }
+  }
+};
+fibonacci(35);
+`
+
+func main() {
+	flag.Parse()
+
+	var duration time.Duration
+	var result object.Object
+
+	l := lexer.New(input)
+	p := parser.New(l)
+	program := p.ParseProgram()
+
+	if *engine == "vm" {
+		comp := compiler.New()
+		err := comp.Compile(program)
+		if err != nil {
+			fmt.Printf("compiler error: %s", err)
+			return
+		}
+
+		machine := vm.New(comp.Bytecode())
+
+		start := time.Now()
+
+		err = machine.Run()
+		if err != nil {
+			fmt.Printf("vm error: %s", err)
+			return
+		}
+
+		duration = time.Since(start)
+		result = machine.LastPoppedStackElem()
+	} else {
+		env := object.NewEnvironment()
+		start := time.Now()
+		result = evaluator.Eval(program, env)
+		duration = time.Since(start)
 	}
-	fmt.Printf("Hello %s! This is the Monkey programmig language!\n", user.Username)
-	fmt.Printf("Feel free to type in commands\n")
-	repl.Start(os.Stdin, os.Stdout)
+
+	fmt.Printf(
+		"engine=%s, result=%s, duration=%s\n",
+		*engine,
+		result.Inspect(),
+		duration)
 }
diff --git a/vm/vm_test.go b/vm/vm_test.go
index 395eca4..ce05909 100644
--- a/vm/vm_test.go
+++ b/vm/vm_test.go
@@ -755,3 +755,27 @@ func TestRecursiveFunctions(t *testing.T) {
 
 	runVmTests(t, tests)
 }
+
+func TestRecursiveFibonacci(t *testing.T) {
+	tests := []vmTestCase{
+		{
+			input: `
+        let fibonacci = fn(x) {
+            if (x == 0) {
+                return 0;
+            } else {
+                if (x == 1) {
+                    return 1;
+                } else {
+                    fibonacci(x - 1) + fibonacci(x - 2);
+                }
+            }
+        };
+        fibonacci(15);
+        `,
+			expected: 610,
+		},
+	}
+
+	runVmTests(t, tests)
+}