react-native/ReactCommon/cxxreact/JsArgumentHelpers-inl.h

91 lines
2.7 KiB
C++

// Copyright 2004-present Facebook. All Rights Reserved.
#pragma once
namespace facebook {
namespace xplat {
namespace detail {
template <typename R, typename M, typename... T>
R jsArg1(const folly::dynamic& arg, M asFoo, const T&... desc) {
try {
return (arg.*asFoo)();
} catch (const folly::TypeError& ex) {
throw JsArgumentException(
folly::to<std::string>(
"Error converting javascript arg ", desc..., " to C++: ", ex.what()));
} catch (const std::range_error& ex) {
throw JsArgumentException(
folly::to<std::string>(
"Could not convert argument ", desc..., " to required type: ", ex.what()));
}
}
}
template <typename R, typename... T>
R jsArg(const folly::dynamic& arg, R (folly::dynamic::*asFoo)() const, const T&... desc) {
return detail::jsArg1<R>(arg, asFoo, desc...);
}
template <typename R, typename... T>
R jsArg(const folly::dynamic& arg, R (folly::dynamic::*asFoo)() const&, const T&... desc) {
return detail::jsArg1<R>(arg, asFoo, desc...);
}
template <typename T>
typename detail::is_dynamic<T>::type& jsArgAsDynamic(T&& args, size_t n) {
try {
return args[n];
} catch (const std::out_of_range& ex) {
// Use 1-base counting for argument description.
throw JsArgumentException(
folly::to<std::string>(
"JavaScript provided ", args.size(),
" arguments for C++ method which references at least ", n + 1,
" arguments: ", ex.what()));
}
}
template <typename R>
R jsArgN(const folly::dynamic& args, size_t n, R (folly::dynamic::*asFoo)() const) {
return jsArg(jsArgAsDynamic(args, n), asFoo, n);
}
template <typename R>
R jsArgN(const folly::dynamic& args, size_t n, R (folly::dynamic::*asFoo)() const&) {
return jsArg(jsArgAsDynamic(args, n), asFoo, n);
}
namespace detail {
// This is a helper for jsArgAsArray and jsArgAsObject.
template <typename T>
typename detail::is_dynamic<T>::type& jsArgAsType(T&& args, size_t n, const char* required,
bool (folly::dynamic::*isFoo)() const) {
T& ret = jsArgAsDynamic(args, n);
if ((ret.*isFoo)()) {
return ret;
}
// Use 1-base counting for argument description.
throw JsArgumentException(
folly::to<std::string>(
"Argument ", n + 1, " of type ", ret.typeName(), " is not required type ", required));
}
} // end namespace detail
template <typename T>
typename detail::is_dynamic<T>::type& jsArgAsArray(T&& args, size_t n) {
return detail::jsArgAsType(args, n, "Array", &folly::dynamic::isArray);
}
template <typename T>
typename detail::is_dynamic<T>::type& jsArgAsObject(T&& args, size_t n) {
return detail::jsArgAsType(args, n, "Object", &folly::dynamic::isObject);
}
}}