Buffer.connectUndo

gulong connectUndo(T)(T callback,  Flag!"After" after =  No.After) if (isCallable!T
    &&  is(ReturnType!T ==  void)
   && (Parameters!T.length <  1 || (ParameterStorageClassTuple!T[0]  ==  ParameterStorageClass.none &&  is(Parameters!T[0] :  gtksource.buffer.Buffer)))
   &&  Parameters!T.length <  2)

Connect to Undo signal.

The ::undo signal is emitted to undo the last user action which modified the buffer.

Parameters

`callback`	signal callback delegate or function to connect `void callback(gtksource.buffer.Buffer buffer)` `buffer` the instance the signal is connected to (optional)
`after`	Yes.After to execute callback after default handler, No.After to execute before (default)

Returns

Signal ID