I get a compiler regarding apply_visitor within the current operator.
I tested all the apply_visitor outside of that method and it works perfectly fine. Just when trying to use it within that method it runs into a bunch of issues.
The error message is confusing me.
So, Why is trying to use apply_visitor for a different visitor is running into problems within the current visitor?
Here the Snippet of the code that have give me the errors:
typedef boost::make_recursive_variant<string, int, vector<boost::recursive_variant_ > >::type ObjectE;
class ReturnType : public boost::static_visitor<string> {
public:
string operator()(string &s) { return "string"; }
string operator()(int i) {return "int";}
string operator()(std::vector<ObjectE> const &v) {return "vector";}
};
class ReturnVal : public boost::static_visitor<string> {
public:
string operator()(string &s) { return s; }
string operator()(int i) {return to_string(i);}
string operator()(std::vector<ObjectE> const &v) {return "vector";}
};
class ReturnV : public boost::static_visitor<vector<ObjectE>> {
public:
vector<ObjectE> operator()(string &s){ return {};}
vector<ObjectE> operator()(int i) {return {};}
vector<ObjectE> operator()(vector<ObjectE> const &v) {return v;}
};
struct create_Str {
using result_type = void;
std::ostream & out;
template <typename T> void call(T const &v) { return operator()(v);}
template <typename... Ts> void operator()(boost::variant<Ts...> const &v) {
return boost::apply_visitor(*this, v);
}
void operator()(int i) { out << i; }
void operator()(std::string const &s) { out << s; }
template <typename... Ts> void operator()(std::vector<Ts...> const &v) {
string name = boost::apply_visitor(ReturnVal(), v[0]);
if (v.size() == 3 && isOp(name)) {
}
else if (v.size() == 3 && isListCons(name)) {
call(v[1]);
ObjectE tail = v[2];
for (;;) {
if ("[]" == boost::get<string>(tail) || "nil" == boost::get<string>(tail)) {
break;
}
if ( !(boost::apply_visitor(ReturnType(), tail) == "vector")) {
}
vector<ObjectE> list = boost::apply_visitor(ReturnV(), v[2]);;
if (!(list.size() == 3 && isListCons(boost::apply_visitor(ReturnVal(), list[0])))) {
}
}
}
}
};
At first, I thought maybe
vector<ObjectE> list = v[2];
was the issue. So I created a visitor who will return a vector.
However, it seem that most of the errors are :
error: no match for call to '(const ReturnVal) (std::__cxx11::basic_string<char>&)'
which I'm not sure what it mean.
Can someone explain to me what the issue is?
