[cvs-nhc98] patch applied (hat): Tidy up SExp code, in particular to put back necessary parentheses in

[Malcolm Wallace]

Sun Apr 17 06:44:31 PDT 2005  malcolm
  * Tidy up SExp code, in particular to put back necessary parentheses in
  pretty-printed expressions.  Also, do not store the result of an
  if/case/guard unless needed (by hat-anim), since storing it
  unnecessarily leads to unbounded resource usage in the other tools.

    M ./src/hattools/HatStack.hs -1 +1
    M ./src/hattools/HatTrail.hs -1 +1
    M ./src/hattools/SExp.hs -172 +187
    M ./src/hattools/VSExp.hs -6 +7