Ascii matters

[Sean Kelly]

On Aug 23, 2012, at 4:25 AM, bearophile <bearophileHUGS at lycos.com> wrote:

> Sean Kelly:
> 
>> Gotcha.  Despite it being something I'd use regularly, I wouldn't want this in Phobos because it seems like it could cause maintenance problems.  I'd rather explicitly cast to ubyte as a way to flag that I was doing something potentially unsafe.
> 
> What's unsafe in what I have presented? The constructor verifies every char to be in 7 bits, and then you use the new type safely. No casts, and no need to flag something as unsafe.
> 
> This usage of types to denote capabilities is quite common in functional languages, see articles I've recently linked here as:
> http://tomasp.net/blog/type-first-development.aspx

So it throws an exception if there are non-ASCII characters in the range?  Is this really better than just casting the input array to ubyte?