Fix Go format

main.go

@@ -1,9 +1,9 @@
 package main
 
 import (
-  "fmt"
+	"fmt"
-  "sync"
+	"sync"
-  "unsafe"
+	"unsafe"
 )
 
 /*
@@ -18,28 +18,30 @@ import "C"
 
 //export callOnMeGo
 func callOnMeGo(n int) {
-  printerCallback(n)
+	printerCallback(n)
 }
 
 type Printer func(int)
 
-var printerCallback Printer
+var (
-var printerCallbackLock sync.RWMutex
+	printerCallback     Printer
+	printerCallbackLock sync.RWMutex
+)
 
 func usePrinter(p Printer) {
-  printerCallbackLock.Lock()
+	printerCallbackLock.Lock()
-  printerCallback = p
+	printerCallback = p
-  C.use_printer((C.printer_t)(unsafe.Pointer(C.callOnMeGo_cgo)))
+	C.use_printer((C.printer_t)(unsafe.Pointer(C.callOnMeGo_cgo)))
-  printerCallback = nil
+	printerCallback = nil
-  printerCallbackLock.Unlock()
+	printerCallbackLock.Unlock()
 }
 
 var myPrinter Printer = Printer(func(n int) {
-  for i := 0; i < n; i++ {
+	for i := 0; i < n; i++ {
-    fmt.Printf("%d\n", i)
+		fmt.Printf("%d\n", i)
-  }
+	}
 })
 
 func main() {
-  usePrinter(myPrinter)
+	usePrinter(myPrinter)
 }