(use tree-rewrite)

(define rule-bool
  `( 
    ( (M or true $x) => true )

    ( (M or $x true ) => true )

    ( (M or false $x) => $x )

    ( (M or $x false ) => $x )

    ( (M not false ) => true )

    ( (M not true ) => false )

    ( (M not $x ) => false )

    ( (M if true $x $y) => $x )

    ( (M if false $x $y) => $y )
    
    ))