Question on Part V in Let's Build a Compiler

I'm working through Let's Build a Compiler (http://compilers.iecc.com/crenshaw/
) and I've run into a problem. The definition of Block after the first
iteration of DoIf is:


procedure Block;
begin
        while not(Look in ['e']) do begin
              case Look of
                'i': DoIf;
                'o': Other;
              end;
        end;
end;


This seems to go into an infinite loop if Look is anything other than
'e', 'i', or 'o'.


The definition after DoWhile is introduced works correctly:


procedure Block;
begin
        while not(Look in ['e', 'l']) do begin
              case Look of
                'i': DoIf;
                'w': DoWhile;
                else Other;
              end;
        end;
end;


Should the 'o:' case in the first version actually be 'else'?


-Steve

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