terminfo__set_background__parsing

setb=%?%p1%{7}%>%t\E[48;5;%p1%dm%e\E[4%?%p1%{1}%=%t4%e%p1%{3}%=%t6%e%p1%{4}%=%t1%e%p1%{6}%=%t3%e%p1%d%;m%;

# Doc: http://invisible-island.net/ncurses/man/terminfo.5.html#h3-Parameterized-Strings

setb=
  %?          # start new if
    %p1       # stack.push arg1
    %{7}      # stack.push 7
    %>        # stack.push(stack.pop > stack.pop)    # pop are in reverse order

  %t          # if arg1 > 7           (if stack.pop != 0)
    \E[48;5;  #   print '\E[48;5;'
    %p1       #   stack.push arg1
    %d        #   print stack.pop
    m         #   print 'm'
  %e          # else
    \E[4      #   print '\E[4'

    %?        #   start new if
      %p1     #   stack.push arg1
      %{1}    #   stack.push 1
      %=      #   stack.push(stack.pop > stack.pop)    # pop are in reverse order
    %t        #   if arg1 == 1        (if stack.pop != 0)
      4       #     print '4'
    %e        #   else
      %p1
      %{3}
      %=
    %t        #   if arg1 == 3        (if stack.pop != 0)
      6       #     print '6'
    %e        #   else
      %p1
      %{4}
      %=
    %t        #   if arg1 == 4        (if stack.pop != 0)
      1       #     print '1'
    %e        #   else
      %p1
      %{6}
      %=
    %t        #   if arg1 == 6        (if stack.pop != 0)
      3       #     print '3'
    %e        #   else
      %p1     #     stack.push arg1
      %d      #     print arg1
    %;        #   endif
    m         #   print 'm'
  %;          # endif