From: Logan Capaldo <logancapaldo@...>
Date: 2006-01-21T05:35:30+09:00
Subject: Re: Hungarian Case variable names.


On Jan 20, 2006, at 2:13 PM, James Edward Gray II wrote:

> On Jan 20, 2006, at 12:21 PM, Zach wrote:
>
>> Does anyone see advantages to using Hungarian Case to variable  
>> names in
>> Ruby, or do you think it may hinder as some people call "accidental
>> abstraction" [Bill Davis] ?
>
> I assume you know this, but just to be sure, Joel on Software has a  
> semi-famous article about the virtues of Hungarian Notation:
>
> http://www.joelonsoftware.com/articles/Wrong.html
>
> If you make it all the way to the end of that, it talks about how  
> the notation is intended to show a "kind", not "type".  When used  
> that way, I can't decide if it interferes with Duck Typing or  
> not...  A great example is escaping me.
>
> It may indeed be useful, but it is hard to argue that it isn't  
> ugly.  ;)
>
> James Edward Gray II
>
>

As I was reading this, all I kept thinking of was ML/Haskell. In  
pseudo ML:

type unsafe_string = UString of string
type safe_string = SString of string

Request :: string -> unsafe_string
Encode :: unsafe_string -> safe_string
Write :: safe_string -> unit

etc..

Now the compiler is tracking all this junk for you. I realize this is  
the land of duck-typing, but I think if the type-inference is good  
enough, you can have your cake and eat it too.