From: Matt Armstrong <matt@...>
Date: 2003-02-13T08:50:34+09:00
Subject: Re: Should substrings be modifiable in-place??

"Hal E. Fulton" <hal9000@hypermetrics.com> writes:

> I've been thinking about this for a half hour or so.
>
> Rather than writing this kind of thing:
>
>   str[x,y] = str[x,y].reverse
>   str[x..z] = str[x..z].reverse
>
> I'd like to be able to do this:
>
>   str[x,y].reverse!
>   str[x..z].reverse!
>
> There is probably some good reason this won't work, though. ;)
>
> Someone care to comment?

Implementation problems.  The reverse! must be sent to some object --
presumably a "Substring" object that can modify the string it
contains.  But I'm not sure str#[] should return a non-String.

I would love a Substring class, as it would make some of the things I
have done in the past easier to write and more efficient.  But
sometimes I would want modifications to self to modify the owning
string, sometimes not.

-- 
matt