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From: Vladimir Prus (ghost_at_[hidden])
Date: 2004-04-05 00:55:49


Hi Jeremy,

>> The problem is that if a graph don't privde vertex index property,
>> then it's
>> not possible to create efficient external property map -- the only way
>> I
>> know is std::map, which is not as fast as property maps which use
>> indices.
>
> Is there some reason you want to have a graph without a vertex index
> property
> and also use external property maps? If not, just use graph a with a
> vertex
> index internal property. Or am I missing something?

The issue is for all types of graph that don't use vecS for vertices
storage, you need to manually initialize vertex index (or am I mistaked?).
I looks like a big inconvenience for me, so I basically always assume
that I use vecS.

>> Ah, but the documentation does not say that std::string is convertible
>> to
>> property<vertex_name_t,std::string>("brother"), at least I can't find
>> it.
>
> Oops, there's lots of stuff missing from the docs for property. I've
> checked in a bunch of additions.

Thanks! The updated docs now answer my question.

>> Another idea: isn't this a good application for named function
>> parameters?
>>
>> add_vertex(g, vertex_name_t("brother").vertex_index_t(10));
>>
>> ? I'm still in dark about named parameters used by BGL or the upcoming
>> named
>> param library, so is not sure if this exact syntax is implementable.
>
> That's a good idea.

Ok, placed to the ideas bag ;-) Hopefully one day we can grab it from there
and implement -- though need to understand what other users want.

- Volodya


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