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From: "FabienFleutot" <fleutotf@esiee.fr>
To: <leary@nwlink.com>, "David Fox" <dsf@foxthompson.net>
Cc: "caml" <caml-list@inria.fr>
References: <20010616170909.B10922@jean> <lun177m88f.fsf@dsf.net>
Subject: Re: [Caml-list] Newbie: declarations
Date: Mon, 18 Jun 2001 16:52:06 +0200
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From: "David Fox" <dsf@foxthompson.net>
> leary@nwlink.com writes:
>
> > Is there a way to declare a variable and not initialize it, like C?
> >
> > int i;
> > i = 0;
> >
> > More to the point, is there a way to declare a record variable without
> > listing/initializing all the fields?  If yes, what are the default
values?
>
[...]
> My first pass solution is to create a reference
> to a dummy object:
>
> let dummy = {field1=0; field2=0...}
> let current = ref dummy

A better solution would be to use options. If it is possible for some of
your vars to be uninitialized, this unitialized state should be able to be
easily filtered:

let current = ref None;
...
current := Some(generate_struct foo bar);
...
match current with
| None -> failwith "This shouldn't be uninitializable at this stage."
| Some current ->
   ...

It's way cleaner than if(!current==dummy) tests.
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