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[Caml-list] assertions or exceptions?
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Date: -- (:)
From: John Carr <jfc@m...>
Subject: Re: [Caml-list] Unboxing options, was RE: assertions or exceptions?

> > One of the problems with returning error conditions instead of throwing
> > exceptions is the cost of boxing a 'a option.  I'd like to advocate for
> > the idea of unboxing 'a options.
> 
> This has been discussed before.  The essential problem is this:
> 
> Currently:
> 
> type 'a option is not the same as type 'a option option
> Some Some 1 is not the same as Some 1
> Some None is not the same as None
> 
> With unboxed options:
> 
> type 'a option is the same as type 'a option option
> Some Some 1 is identical to Some 1
> Some None is identical to None

So use true 0 as opposed to the integer 0 internally represented as 1
to mean "None".  This adds some complexity but may be worth the effort
as options are common.

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