//$Id$

//X/$module Stream-Position;

$use Access Arithm;

//** $func Init-Position e.name = t.position;

Init_Position e.name = ((e.name) (1 1));


//** $func Name   t.position = e.name;
//** $func Row    t.position = s.row;
//** $func Column t.position = s.column;

Name   ((e.name) t) = e.name;
Row    (t.name (s.row s.col)) = s.row;
Column (t.name (s.row s.col)) = s.col;


/*
$func Next-Column t.position = t.position;
$func Next-Row    t.position = t.position;

Next-Column (t.name (s.row s.col)) = (t.name (s.row <"+" s.col 1>));
Next-Row    (t.name (s.row s.col)) = (t.name (<"+" s.row 1> 1));
*/


//** $func Advance-Pos t.position expr = t.position;
//** $func Relapse-Pos t.position expr = t.position;

Advance_Pos (t.name (s.row s.col)) expr, expr : {
  e1 '\n' e2 = <Advance_Pos (t.name (<Add s.row 1> 1)) e2>;
  e1         = (t.name (s.row <Add s.col <Length e1>>));
};

Relapse_Pos (t.name (s.row s.col)) expr, expr : {
  $r e1 '\n' e2 = <Advance_Pos (t.name (<Sub s.row 1> 1)) e1>;
  e1            = (t.name (s.row <Sub s.col <Length e1>>));
};