Re: [Boost-Users] Re: [BGL] Property map question

From: Jeremy Siek (jsiek_at_[hidden])
Date: 2002-09-15 21:42:05

Hi Chris,

On Sun, 15 Sep 2002, Chris Russell wrote:
cdr> What determines when boost::get(Graph, vertex_myproperty_t) returns a
cdr> boost::property_map<graph_t, vertex_myproperty>::type vs. a
cdr> ::const_type?

The constness of the graph object that is passed to get().

cdr> vertex_myproperty_map_t MyMap = get(vertex_myproperty, Graph);
cdr>
cdr> ^--- this works as I expected. However, if I try to get a copy of my
cdr> property map this way inside a dfs visitor method, my compiler tells
cdr> me that
cdr> there's no suitable conversion from property_map<graph_t,
cdr> vertex_myproperty_t>::const_type to property_map<graph_t,
cdr> vertex_myproperty_t>::type (IA32 6.0 Intel compiler).

You've got a const graph object inside the visitor, so you need to use the
const property map.

Cheers,
Jeremy

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 Jeremy Siek                          http://php.indiana.edu/~jsiek/
 Ph.D. Student, Indiana Univ. B'ton   email: jsiek_at_[hidden]
 C++ Booster (http://www.boost.org)   office phone: [phone]
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