anchor.diff:  
   -compile(export_all).
   
  +-define(Mach_Eps, 1.1920928955078125e-7).
   -define(NotYetImplemented(Cond,Prop),?IMPLIES(not (Cond),Prop)).
   
   %% eqc_gen:sample(protobuffs_eqc:field_num()).
  
positive.code: 			     {{N, RData}, <<>>} = protobuffs:decode(list_to_binary(Bin), Type),
      			 in_range(Data,Type) andalso
      			     FieldNum=:=N andalso
      			     (Data==RData orelse foreign_type(Type,Data,RData))  
  	     end).
  
  prop_encode_decode() ->
  
negative.code:     fitbits(abs(Int),63);
  in_range(Int,uint64) ->
      fitbits(Int,64);
  in_range(Float,float) ->
      fitbits(Float,32);
  in_range(Float,double) ->
      fitbits(Float,64);
  in_range(false,bool) ->
      true;
  in_range(true,bool) ->
      true.
  
  compare(Float1, Float2) when is_float(Float1), is_float(Float2) ->
      (abs(Float1 - Float2) =< ?Mach_Eps);
  compare(A,A) -> true;
  compare(_,_) -> false.
      
  fitbits(Float,32) when is_float(Float) -> true;
  fitbits(Float,64) when is_float(Float) -> true;
  fitbits(Int,Bits) ->
      RestBits = 80-Bits,
      << NoFit:RestBits, _:Bits >> = <<Int:80>>,
  