Re: [boost] Re: lexical_cast "Future directions"

From: Kevlin Henney (kevlin_at_[hidden])
Date: 2002-12-30 10:29:37

In message <u7kdsjwcc.fsf_at_[hidden]>, David Abrahams
<dave_at_[hidden]> writes
>"Early Ehlinger" <earlye_at_[hidden]> writes:
>
>> [Sorry for the top-posted reply... OE is giving me fits...]
>>
>> This is an interesting argument.  In other words, lexical_cast is,
>> by definition, conversion through a stream.  Therefore, one cannot
>> expect a string with whitespace to exit as it went in.
>>
>> Perhaps what is really needed is a different pseudo-cast, e.g.,
>> symantic_cast< >, which has different goals more in synch with what
>> we are trying to accomplish, which is conversion from any type to
>> another with minimized loss of symantic value.
>
>This is the philosophy that Kevlin and I agreed on when lexical_cast
>was first introduced.  However, I don't think it has stood the test of
>time with real users, and it would be stupid to ignore that.  I
>suspect Kevlin feels the same way about it, which is why he has agreed
>to review the changes in the Files area.  

Apologies for delays. Yes, I have to review Terje's changes and am
guilty of not having applied myself to that task yet. In terms of the
philosophy of the design, I think it would be reasonable to say that
intuitive stream-based conversion is the aim, which is compatible with
fixing whitespace issues. However, other type-to-type conversions
outside of that realm generally don't fit with either the strict or
loose interpretation of that design. A placeholder idea, namely
interpret_cast (the original name of lexical_cast), is mentioned in the
docs for smarter and more varied type conversions. However, the concrete
demand for this feature has been as close to zero as arithmetic
underflow.

>I also suspect family and
>work have been keeping him busy, which is why he hasn't done it yet
>;-).
>
>I'd love to stop speculating and hear from Kevlin himself, though ;-) ;-)

Family have been a constant source of amusement and colds, and work has
been unseasonally busy -- or rather, given the current economic climate,
it has econometeorologically atypical :->

Kevlin
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