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Re: Opacity considered harmful
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