diff --git a/.gitignore b/.gitignore
deleted file mode 100644
index d128cc4..0000000
--- a/.gitignore
+++ /dev/null
@@ -1,2 +0,0 @@
-*.exe
-*.tmp
diff --git a/char.go b/char.go
deleted file mode 100644
index e269640..0000000
--- a/char.go
+++ /dev/null
@@ -1,36 +0,0 @@
-package readline
-
-const (
-	CharLineStart = 1
-	CharBackward  = 2
-	CharInterrupt = 3
-	CharDelete    = 4
-	CharLineEnd   = 5
-	CharForward   = 6
-	CharBell      = 7
-	CharCtrlH     = 8
-	CharTab       = 9
-	CharCtrlJ     = 10
-	CharKill      = 11
-	CharCtrlL     = 12
-	CharEnter     = 13
-	CharNext      = 14
-	CharPrev      = 16
-	CharBckSearch = 18
-	CharFwdSearch = 19
-	CharTranspose = 20
-	CharCtrlU     = 21
-	CharCtrlW     = 23
-	CharCtrlZ     = 26
-	CharEsc       = 27
-	CharEscapeEx  = 91
-	CharBackspace = 127
-)
-
-const (
-	MetaBackward rune = -iota - 1
-	MetaForward
-	MetaDelete
-	MetaBackspace
-	MetaTranspose
-)
diff --git a/complete.go b/complete.go
index 75f7f68..75b38af 100644
--- a/complete.go
+++ b/complete.go
@@ -18,6 +18,12 @@ type AutoCompleter interface {
 	Do(line []rune, pos int) (newLine [][]rune, length int)
 }
 
+type TabCompleter struct{}
+
+func (t *TabCompleter) Do([]rune, int) ([][]rune, int) {
+	return [][]rune{[]rune("\t")}, 0
+}
+
 type opCompleter struct {
 	w     io.Writer
 	op    *Operation
diff --git a/complete_tag.go b/complete_tag.go
deleted file mode 100644
index 2039458..0000000
--- a/complete_tag.go
+++ /dev/null
@@ -1,7 +0,0 @@
-package readline
-
-type TabCompleter struct{}
-
-func (t *TabCompleter) Do([]rune, int) ([][]rune, int) {
-	return [][]rune{[]rune("\t")}, 0
-}
diff --git a/debug.go b/debug.go
deleted file mode 100644
index 7878500..0000000
--- a/debug.go
+++ /dev/null
@@ -1,29 +0,0 @@
-package readline
-
-import (
-	"container/list"
-	"fmt"
-	"os"
-	"time"
-)
-
-func sleep(n int) {
-	Debug(n)
-	time.Sleep(2000 * time.Millisecond)
-}
-
-// print a linked list to Debug()
-func debugList(l *list.List) {
-	idx := 0
-	for e := l.Front(); e != nil; e = e.Next() {
-		Debug(idx, fmt.Sprintf("%+v", e.Value))
-		idx++
-	}
-}
-
-// append log info to another file
-func Debug(o ...interface{}) {
-	f, _ := os.OpenFile("debug.tmp", os.O_RDWR|os.O_CREATE|os.O_APPEND, 0666)
-	fmt.Fprintln(f, o...)
-	f.Close()
-}
diff --git a/doc.go b/doc.go
deleted file mode 100644
index 656d6ca..0000000
--- a/doc.go
+++ /dev/null
@@ -1,20 +0,0 @@
-// Readline is a pure go implementation for GNU-Readline kind library.
-//
-// WHY: Readline will support most of features which GNU Readline is supported, and provide a pure go environment and a MIT license.
-//
-// example:
-// 	rl, err := readline.New("> ")
-// 	if err != nil {
-// 		panic(err)
-// 	}
-// 	defer rl.Close()
-//
-// 	for {
-// 		line, err := rl.Readline()
-// 		if err != nil { // io.EOF
-// 			break
-// 		}
-// 		println(line)
-// 	}
-//
-package readline
diff --git a/readline.go b/readline.go
index 20a2108..14af1dd 100644
--- a/readline.go
+++ b/readline.go
@@ -1,3 +1,20 @@
+// Readline is a pure go implementation for GNU-Readline kind library.
+//
+// example:
+// 	rl, err := readline.New("> ")
+// 	if err != nil {
+// 		panic(err)
+// 	}
+// 	defer rl.Close()
+//
+// 	for {
+// 		line, err := rl.Readline()
+// 		if err != nil { // io.EOF
+// 			break
+// 		}
+// 		println(line)
+// 	}
+//
 package readline
 
 import "io"
diff --git a/utils.go b/utils.go
index 6084a7d..96518f1 100644
--- a/utils.go
+++ b/utils.go
@@ -3,6 +3,9 @@ package readline
 import (
 	"bufio"
 	"bytes"
+	"container/list"
+	"fmt"
+	"os"
 	"strconv"
 	"strings"
 	"sync"
@@ -14,6 +17,41 @@ var (
 	isWindows = false
 )
 
+const (
+	CharLineStart = 1
+	CharBackward  = 2
+	CharInterrupt = 3
+	CharDelete    = 4
+	CharLineEnd   = 5
+	CharForward   = 6
+	CharBell      = 7
+	CharCtrlH     = 8
+	CharTab       = 9
+	CharCtrlJ     = 10
+	CharKill      = 11
+	CharCtrlL     = 12
+	CharEnter     = 13
+	CharNext      = 14
+	CharPrev      = 16
+	CharBckSearch = 18
+	CharFwdSearch = 19
+	CharTranspose = 20
+	CharCtrlU     = 21
+	CharCtrlW     = 23
+	CharCtrlZ     = 26
+	CharEsc       = 27
+	CharEscapeEx  = 91
+	CharBackspace = 127
+)
+
+const (
+	MetaBackward rune = -iota - 1
+	MetaForward
+	MetaDelete
+	MetaBackspace
+	MetaTranspose
+)
+
 // WaitForResume need to call before current process got suspend.
 // It will run a ticker until a long duration is occurs,
 // which means this process is resumed.
@@ -211,3 +249,26 @@ func (r *RawMode) Exit() error {
 	}
 	return Restore(GetStdin(), r.state)
 }
+
+// -----------------------------------------------------------------------------
+
+func sleep(n int) {
+	Debug(n)
+	time.Sleep(2000 * time.Millisecond)
+}
+
+// print a linked list to Debug()
+func debugList(l *list.List) {
+	idx := 0
+	for e := l.Front(); e != nil; e = e.Next() {
+		Debug(idx, fmt.Sprintf("%+v", e.Value))
+		idx++
+	}
+}
+
+// append log info to another file
+func Debug(o ...interface{}) {
+	f, _ := os.OpenFile("debug.tmp", os.O_RDWR|os.O_CREATE|os.O_APPEND, 0666)
+	fmt.Fprintln(f, o...)
+	f.Close()
+}