Cfrgtkky

I am currently getting acquainted with Leslie Lamports pf2.sty
(http://lamport.azurewebsites.net/latex/latex.html).

Which unfortunately is not on CTAN.

It intents to encourage a certain proof style, which Lamport calls
hierarchical proof.

A proof looks then a lot as nested enumerate environments

The pf2.sty package itself is not so comfortable and most of its
features can be achieved by using the enumitem package.

However there is one useful feature which I don't know how to implement
in vanilla latex, namely hide/show parts of the nested proofs.

Here is an example (presuming you have pf.sty

 documentclass[12pt]{article}

 usepackage{pf2}

 begin{document}

 pfhidelevel{1}

 begin{proof}

   step{item:test-lamport2:1b}{Text of step 1.}

   begin{proof}

     step{label-1.1}{Text of substep 1} 

      begin{proof}

        pf Paragraph proof using results in stepref{label-1.1} .~qed

      end{proof}

     step{label-2.1}{Text of substep 2}

    end{proof}

    step{label-2.2}{Text of step 2} 

  end{proof}

end{document}

so only text of step 1 and 2 are displayed after compiling, if I chose
pfhidelevel{2}, then also the next level will be shown etc.

Now to my enumitem solution

 documentclass[12pt]{article}

 usepackage{amsmath,amssymb}

 usepackage{enumitem}

 setenumerate[1]{label=$langle$1$rangle$arabic*., ref=$langle$1$rangle$arabic*}

 setenumerate[2]{label=$langle$2$rangle$arabic*., ref=$langle$1$rangle$ref=arabic*}

 begin{document}





  begin{enumerate}

    item label{item:test-lamport2:1b}{Text of step 1.}

    begin{enumerate}

      item label{item:solution-enumitem:1} Text of substep 1

       begin{enumerate}

         item[textsc{PROOF}] Paragraph proof using results in

         ref{item:solution-enumitem:1}. $blacksquare$

       end{enumerate}

      item label{label-2.1}{Text of substep 2}

     end{enumerate}

     item label{label-2.2}{Text of step 2} 

   end{enumerate}

 end{document}

Uwe Brauer

Something like this

documentclass[12pt]{article}

 usepackage{amsmath,amssymb}

 usepackage{enumitem}

 setenumerate[1]{label=$langle$1$rangle$arabic*., ref=$langle$1$rangle$arabic*}

 setenumerate[2]{label=$langle$2$rangle$arabic*., ref=$langle$1$rangle$ref=arabic*}



newcountpflevel

newcommandpfhidelevel[1]{pflevel=#1relax}

letzzenumerateenumerate

makeatletter

defenumerate{%

ifnumpflevel=@enumdepth

setbox0vboxbgroupbegingroupaftergroupegroupaftergroupendgroup

fi

zzenumerate}

 begin{document}



00000



  begin{enumerate}

    item label{item:test-lamport2:1b}{Text of step 1.}

    begin{enumerate}

      item label{item:solution-enumitem:1} Text of substep 1

       begin{enumerate}

         item[textsc{PROOF}] Paragraph proof using results in

         ref{item:solution-enumitem:1}. $blacksquare$

       end{enumerate}

      item label{label-2.1}{Text of substep 2}

     end{enumerate}

     item label{label-2.2}{Text of step 2} 

   end{enumerate}



111111





pfhidelevel{1}

  begin{enumerate}

    item label{item:test-lamport2:1b}{Text of step 1.}

    begin{enumerate}

      item label{item:solution-enumitem:1} Text of substep 1

       begin{enumerate}

         item[textsc{PROOF}] Paragraph proof using results in

         ref{item:solution-enumitem:1}. $blacksquare$

       end{enumerate}

      item label{label-2.1}{Text of substep 2}

     end{enumerate}

     item label{label-2.2}{Text of step 2} 

   end{enumerate}







2222222





pfhidelevel{2}

  begin{enumerate}

    item label{item:test-lamport2:1b}{Text of step 1.}

    begin{enumerate}

      item label{item:solution-enumitem:1} Text of substep 1

       begin{enumerate}

         item[textsc{PROOF}] Paragraph proof using results in

         ref{item:solution-enumitem:1}. $blacksquare$

       end{enumerate}

      item label{label-2.1}{Text of substep 2}

     end{enumerate}

     item label{label-2.2}{Text of step 2} 

   end{enumerate}

 end{document}