json/api/macros/json_noexception/index.md

JSON_NOEXCEPTION

#define JSON_NOEXCEPTION

Exceptions can be switched off by defining the symbol JSON_NOEXCEPTION. When defining JSON_NOEXCEPTION, try is replaced by if (true), catch is replaced by if (false), and throw is replaced by std::abort().

The same effect is achieved by setting the compiler flag -fno-exceptions.

Default definition

By default, the macro is not defined.

#undef JSON_NOEXCEPTION

Notes

The explanatory what() string of exceptions is not available for MSVC if exceptions are disabled, see #2824.

Examples

Example

The code below switches off exceptions in the library.

#define JSON_NOEXCEPTION 1
#include <nlohmann/json.hpp>

...

See also

• Switch off exceptions - more information how to switch off exceptions
• Supported Macros - guide to all supported macros
• Working Without Exceptions - using the library without exceptions
• Exceptions - all exceptions and their error codes
• exception - base class of all exceptions thrown by the library

Version history

Added in version 2.1.0.