adding in file path option

option.go

@@ -1,9 +1,28 @@
 package lite
 
-type Option func(d *database)
+import (
+	"fmt"
+)
+
+var (
+	ErrBadFilename error = fmt.Errorf("database filename cannot be empty")
+)
+
+type Option func(d *database) error
 
 func WithFile(name string) Option {
-	return func(d *database) {
+	return func(d *database) error {
+		if name == "" {
+			return ErrBadFilename
+		}
 		d.file = name
+		return nil
+	}
+}
+
+func WithPath(path string) Option {
+	return func(d *database) error {
+		d.path = path
+		return nil
 	}
 }