Re: [boost] boost::any: explicit constructor?

From: Kevlin Henney (kevlin_at_[hidden])
Date: 2004-02-26 10:11:32

In message <001901c3fc77$64c7cf70$1d00a8c0_at_pdimov2>, Peter Dimov 
<pdimov_at_[hidden]> writes
>Kevlin Henney wrote:
>>
>> I outlined in a previous email the intended syntax for use. To break
>> this would be more than a little inconvenient, and certainly against
>> the spirit of its design. Making the constructor 'explicit' would
>> break the compilation of other code that is quite reasonable --
>> perhaps not yours, because you are following the style I outlined as
>> an alternative in a previous response -- but it would still break it
>> and for no good reason, eg
>>
>>         std::map<std::string, boost::any> table;
>>         ...
>>         table[key] = 0; // reasonable usage
>
>This use case does not need an implicit constructor, just a templated
>operator=.

It was the spirit and sense of the expression rather than specifically 
the mechanism that I was referring to -- boost::any currently achieves 
this through a templated assignment operator. There was an implied 
(in)consistency that I should perhaps have stressed more clearly.

Kevlin
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