public void Merge(IUndoAction action)
{
EditableEraseAction erase = (EditableEraseAction)action;
if (start == erase.start)
{
text += erase.text;
end += erase.end - erase.start;
}
else
{
text = erase.text + text;
start = erase.start;
}
}
public bool CanMerge(IUndoAction action)
{
EditableEraseAction erase = action as EditableEraseAction;
if (erase == null)
{
return(false);
}
return(!(
is_cut || erase.is_cut || // don't group separate text cuts
start != (is_forward ? erase.start : erase.end) || // must meet eachother
is_forward != erase.is_forward || // don't group deletes with backspaces
text[0] == '\n' || // don't group more than one line (inclusive)
erase.text[0] == ' ' || erase.text[0] == '\t' // don't group more than one word (exclusive)
));
}