Implement clear screen c-l binding

tools/tui/loop/api.go

@@ -252,6 +252,10 @@ func (self *Loop) AllowLineWrapping(allow bool) {
 	}
 }
 
+func (self *Loop) ClearScreen() {
+	self.QueueWriteString("\x1b[H\x1b[2J")
+}
+
 func (self *Loop) Quit(exit_code int) {
 	self.exit_code = exit_code
 	self.keep_going = false

tools/tui/readline/actions.go

@@ -429,7 +429,12 @@ func (self *Readline) perform_action(ac Action, repeat_count uint) error {
 			}
 		}
 		return self.perform_action(ActionCursorDown, repeat_count)
-
+	case ActionClearScreen:
+		self.loop.StartAtomicUpdate()
+		self.loop.ClearScreen()
+		self.RedrawNonAtomic()
+		self.loop.EndAtomicUpdate()
+		return nil
 	}
 	return ErrCouldNotPerformAction
 }

tools/tui/readline/api.go

@@ -55,6 +55,7 @@ const (
 	ActionHistoryNextOrCursorDown
 	ActionHistoryNext
 	ActionHistoryPrevious
+	ActionClearScreen
 )
 
 type Readline struct {

tools/tui/readline/keys.go

@@ -35,6 +35,8 @@ var default_shortcuts = map[string]Action{
 	"right":  ActionCursorRight,
 	"ctrl+f": ActionCursorRight,
 
+	"ctrl+l": ActionClearScreen,
+
 	"ctrl+d": ActionEndInput,
 	"enter":  ActionAcceptInput,
 }