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notebooks - Deleting Print results


While playing around with $Pre and $Post I created this very annoying piece of code:


$Post = If[# =!= 
 Null, (Print@"Are you sure you want to know the result?"; 
 Print@Row@{Button["Yes", Print@#], Button["No", Null]}), Null] &;

I have not yet found a use for it (other than possibly playing pranks on Mma newbies) but it led me to the following question:


How can one delete a certain cell that was created by Print (i.e. without selecting the cell manually)? And furthermore, how can one create a button that deletes itself upon being clicked (still evaluating the action)?


Ultimately I want the button to delete both itself and the "Are you sure..." cell.


I found out in the documentation that PrintTemporary objects can be deleted using NotebookDelete. Is there a similar way for Print cells? I think something similar to what I want could be done using ChoiceDialog and the like, but I'm really interested in deleting the Print cells.




Answer



A self-destructing cell that creates a self-destructing button which deletes all cells generated by Print:
(credit: Sasha, jVincent and Yves Klett for the ideas in answers/comments in the linked Q/As)


Print[Button["Delete Print-generated cells & disappear", 
 NotebookFind[SelectedNotebook[], "Print", All, CellStyle]; NotebookDelete[]]];
 SelectionMove[EvaluationNotebook[], All, EvaluationCell]; NotebookDelete[];

enter image description here


After evaluating the cell


 NotebookFind[SelectedNotebook[], "Print", All, CellStyle];


enter image description here


Note the CellStyles (highlighted) of an ordinary Output cell and that of the one produced by Print.


After evaluating


Print[Button["Delete Print-generated cells & disappear", 
 NotebookFind[SelectedNotebook[], "Print", All, CellStyle]; NotebookDelete[]]];
 SelectionMove[EvaluationNotebook[], All, EvaluationCell]; NotebookDelete[];

enter image description here


After the clicking the button:



enter image description here


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