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c++parsingyaml-cpp

yams-cpp nested sequence returning map instead of value


I am trying to parse the following config.yaml file.

config.yaml

foo:
  bar:
    baz: [1, 2, 3, 4]
    bam: "some_string_value"

test.cpp

YAML::Node configObj = YAML::LoadFile("cfig.yaml"); // loads file just fine

YAML::Node fooObj = configObj["foo"]; // this Node object is a Map

// iterate over foo node to get bar node
for( auto it = fooObj.begin(); it != fooObj.end(); ++it){
    YAML::Node barMap = it->second; // this Node object is a Map

    // iterate over bar node to get bad node
    for( auto i = barMap.begin(); i != barMap.end(); ++i){
        YAML::Node bazMap = i->second; // this node is a sequence

        for( std::size_t i=0; i<bazMap.size(); i++         
            auto index = bazMap[i].as<int>(); // <<< This is the problem
        }
    }
}

The problem as far as I can see is that I am expecting index to be an int but bazMap[i].as<int>() I am expecting to be 1 the first loop, 2 the second, etc. What I am getting instead is bazMap[i].as<int>() is of type map. What am I missing in my understanding here?

Thanks,

Bruce

Update The answer was that I stopped early in my nested for loops.


Solution

  • The answer that I found rests in that I was unclear on what I was getting.

    In the config.yaml file I was expecting the following:

    foo.Type() == Map
    bar.Type() == Sequence
    baz.Type() == Sequence
    

    but what I was getting was:

    foo.Type() == Map
    bar.Type() == Map
    baz.Type() == Sequence
    

    all I had to do to resolve this issue was to change the config file.

    foo:
      bar:
        - baz: [1, 2, 3, 4]
        - bam: "some_string_value"
    

    Then it parsed exactly as I had expected.

    So the issue was the format of the config file and not in the parsing logic.