-------------------------------------------------------------------------
	      |     '0' .. '9'     |    ':'    |       '?'          |  $    |
-------------------------------------------------------------------------
	      |		               |	       |	                |       |
Tern      | '0'..'9' TernTail  |   error   |       error        | error |
          | 	   	           |	       |    	            |       |
-------------------------------------------------------------------------
	      |		               |	       |		            |       |
TernTail  |       error	       |     e     |  '?' Tern ':' Tern |  e    |
	      |	  	               |	       |    	     	    |       |
-------------------------------------------------------------------------
