map_indexing_suite doesn't work with std::unordered_map<std::string, std::vector<double>> for MSVC 14.2

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#289 opened on Jan 30, 2020 1 comment 0 reactions 0 assignees View on GitHub

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Assessment

Difficulty: 3/5
Estimated time: 1-2 days
Newbie friendliness: 38/100

Issue type: Bug
Clarity: Mostly clear
Activity status: Stale
Tech stack: cpp, python
Domain: api

Research direction

Start in boost/python/suite/indexing/map_indexing_suite.hpp at line 155 and reproduce the build with MSVC v142 using the nested std::unordered_map example. Compare it with the std::map and string-value cases described in the report. Done means the map_indexing_suite example builds successfully with the nested unordered_map configuration.

Written by the indexing model from the issue text.

Description

This works on MSVC 14.1 (Visual Studio 17):

#define BOOST_PYTHON_STATIC_LIB

#include <boost/python.hpp>
#include <boost/python/suite/indexing/map_indexing_suite.hpp>
#include <boost/python/suite/indexing/vector_indexing_suite.hpp>
#include <string>
#include <unordered_map>
#include <vector>

BOOST_PYTHON_MODULE(HelloBoostPython)
{
    using namespace boost::python;

    class_<std::vector<double>>("DoubleVector")
        .def(vector_indexing_suite<std::vector<double>>())
        ;

    class_<std::unordered_map<std::string, std::string>>("StringVecMap")
        .def(map_indexing_suite<std::unordered_map<std::string, std::vector<double>>>())
        ;
}

But fails when building against the v142 (VS 19) Platform Toolset:

Severity	Code	Description	Project	File	Line	Suppression State
Error	C2039	'key_comp': is not a member of 'std::unordered_map<std::string,std::vector<double,std::allocator<double>>,std::hash<std::string>,std::equal_to<std::string>,std::allocator<std::pair<const std::string,std::vector<double,std::allocator<double>>>>>'	HelloBoostPython	C:\Misc\boost_1_71_0\boost\python\suite\indexing\map_indexing_suite.hpp	155

Change std::unordered_map to std::map and it works.

Change std::unordered_map<std::string, std::vector<double>> to std::unordered_map<std::string, std::string>> and it works.

Dominant language: C++
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Avg merge: 11h 22m
Merged PRs (30d): 2

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