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What is angle brackets for argument values, and what is it used for?
vector<int> vecOfInts ;

document.Parse<0>(json) ;

template <unsigned parseFlags>
GenericDocument& Parse(const Ch* str) {
    RAPIDJSON_ASSERT(!(parseFlags & kParseInsituFlag));
    GenericStringStream<Encoding> s(str);
    return ParseStream<parseFlags>(s);
}

template <typename T, size_t N> struct Array {
    T arr[N];
};

Array<int, 137> myArray;

std::sort(v.begin(), v.end());

std::sort<vector<int>::iterator>(v.begin(), v.end());

template <unsigned parseFlags>
GenericDocument& Parse(const Ch* str) {
    RAPIDJSON_ASSERT(!(parseFlags & kParseInsituFlag));
    GenericStringStream<Encoding> s(str);
    return ParseStream<parseFlags>(s);
}

Parse<0>(myString);

template <typename Target, typename Source>
    Target lexical_cast(const Source& arg);

std::string myString = boost::lexical_cast<std::string>(toConvertToString);

template <int IntArgument, typename TypeArgment>
    void DoSomething(const TypeArgument& t) {
       /* ... */
}

DoSomething<intArg>(otherArg);