Problem Statement

Quite often one needs loops which, in the last iteration, execute only part of the loop body. Demonstrate the best way to do this. Write a loop which writes the comma-separated list using separate output statements for the number and the comma from within the body of the loop.

Let's start with the solution:

begin
    integer i;
    i := 0;
    while
        begin
           i := i + 1;
           writeon( i );
           i < 10
        end
    do
    begin
       writeon( "," )
    end
end.