anchor.diff:      %a + (%b + %c)
     @>
   
  +let assocSubSub_exp = 
  +  <@
  +    (%a - %b) - %c
  +    <==>
  +    %a - (%b + %c)
  +  @>
  +
   let divide2Mult: Rule = compilePatternToRule divide2Mult_exp
   let distrMult: Rule = compilePatternToRule distrMult_exp
   let constFold0: Rule = compilePatternToRule constFold0_exp
  
positive.code: let multDivide: Rule = compilePatternToRule multDivide_exp
  let assocAddSub: Rule = compilePatternToRule assocAddSub_exp
  let assocAddAdd: Rule = compilePatternToRule assocAddAdd_exp
  
  let letInliner (e: Expr): Expr Option = 
    match e with 
  
negative.code: 
  let multDivide_exp = 
    <@
      %a * (%b / %a)
      <==>
      %b
    @>
  
  let assocAddSub_exp = 
  