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#pragma once
#include <initializer_list> // for initializer_list
#include <string> // for string, basic_string
#include "cpp11/R.hpp" // for SEXP, SEXPREC, Rf_install, PROTECT, Rf_...
#include "cpp11/as.hpp" // for as_sexp
#include "cpp11/protect.hpp" // for protect, safe, protect::function
namespace cpp11 {
class sexp;
template <typename T>
class attribute_proxy {
private:
const T& parent_;
SEXP symbol_;
public:
attribute_proxy(const T& parent, const char* index)
: parent_(parent), symbol_(safe[Rf_install](index)) {}
attribute_proxy(const T& parent, const std::string& index)
: parent_(parent), symbol_(safe[Rf_install](index.c_str())) {}
attribute_proxy(const T& parent, SEXP index) : parent_(parent), symbol_(index) {}
template <typename C>
attribute_proxy& operator=(C rhs) {
SEXP value = PROTECT(as_sexp(rhs));
Rf_setAttrib(parent_.data(), symbol_, value);
UNPROTECT(1);
return *this;
}
template <typename C>
attribute_proxy& operator=(std::initializer_list<C> rhs) {
SEXP value = PROTECT(as_sexp(rhs));
Rf_setAttrib(parent_.data(), symbol_, value);
UNPROTECT(1);
return *this;
}
operator SEXP() const { return safe[Rf_getAttrib](parent_.data(), symbol_); }
};
} // namespace cpp11
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