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Re: Opacity considered harmful
This page is part of the web mail archives of SRFI 76 from before July 7th, 2015. The new archives for SRFI 76 contain all messages, not just those from before July 7th, 2015.
Tony Garnock-Jones wrote:
> Michael Sperber wrote:
>> Without opacity and with reflection,
a client who
gets its hands on a
>> record can get at its fields,
thus breaking the
>> by the maker of that record.
> I see this as an unqualified benefit.
> Sealedness and opacity have given
me nothing but
trouble, and have on
> occasion cost my clients real money.
This sort of dilemma usually tells me
that one should
other alternatives. So how about this
Provide opaque records but also provide
clients with a
mechanism to get to the internal structure
Ideally, the mechanism is highly visible
(syntactically), and too inconvenient
to use 'by
A minimal design for this proposal is
So the final choice is with the client:
opacity, or ignore it.
(The only compelling reason I see to
have the final
the designer of the record type is security,
Mike that SRFI 76 is not the beast to
send into that