Remove '=delete' from template methods for Xcode 8 (#1133)

For Apple clang-800.0.42.1, which was released with Xcode 8 in
September 2016, the '=delete' on the 'is' and 'as' methods causes
the following errors for value.h:

  inline declaration of 'as<bool>' follows non-inline definition
  inline declaration of 'is<bool>' follows non-inline definition

etcetera for the other specializations of 'is' and 'as'.  The same
problem also occurs for clang-3.8 but not clang-3.9 or later.
This commit is contained in:
David Gobbi 2020-02-13 14:22:49 -07:00 committed by GitHub
parent a6fe8e27d8
commit dc180eb25e
No known key found for this signature in database
GPG Key ID: 4AEE18F83AFDEB23

View File

@ -21,6 +21,24 @@
#endif
#endif
// Support for '= delete' with template declarations was a late addition
// to the c++11 standard and is rejected by clang 3.8 and Apple clang 8.2
// even though these declare themselves to be c++11 compilers.
#if !defined(JSONCPP_TEMPLATE_DELETE)
#if defined(__clang__) && defined(__apple_build_version__)
#if __apple_build_version__ <= 8000042
#define JSONCPP_TEMPLATE_DELETE
#endif
#elif defined(__clang__)
#if __clang_major__ == 3 && __clang_minor__ <= 8
#define JSONCPP_TEMPLATE_DELETE
#endif
#endif
#if !defined(JSONCPP_TEMPLATE_DELETE)
#define JSONCPP_TEMPLATE_DELETE = delete
#endif
#endif
#include <array>
#include <exception>
#include <map>
@ -390,8 +408,8 @@ public:
bool isObject() const;
/// The `as<T>` and `is<T>` member function templates and specializations.
template <typename T> T as() const = delete;
template <typename T> bool is() const = delete;
template <typename T> T as() const JSONCPP_TEMPLATE_DELETE;
template <typename T> bool is() const JSONCPP_TEMPLATE_DELETE;
bool isConvertibleTo(ValueType other) const;