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From: Philippe Wang <mail@philippewang.info>
To: Damien Doligez <damien.doligez@inria.fr>
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Subject: Re: [Caml-list] Weird GC behaviour

On Wed, Sep 28, 2011 at 5:30 PM, Damien Doligez <damien.doligez@inria.fr> wrote:

> You should say (Ftag (String.copy "Hello")) if you want a fresh mutable
> string.  I wouldn't recommend appending "" or using Obj.dup (yuck!)
>
> I agree it was a mistake to make strings mutable, but we have to live
> with it for the time being.  If you want to be perfectly safe, you can
> wrap all string literals with String.copy in your program.

If the world tended to be ideal at some point, I'd say it should be a
compiler option, like
   # ocamlopt -unshared-litteral-strings
 (or -shared-literral-strings)
Sometimes it's painful that strings are mutable, but otherwise, it
would be painful too (maybe less often, I don't know). I believe that
the worst is to have *both* mutable strings *and* the necessity to
copy them every time mutability makes it weird.

When I teach programming using OCaml, I really dislike having to
explain that we have to live with this awful semantics (fortunately
the language has stunning great qualities).

Well, I guess this discussion has occurred thousands of times already.
Sorry for that.

Cheers,

-- 
Philippe Wang
   mail@philippewang.info