forked from boostorg/core
82957de970
The uncaught_exceptions function is functionally equivalent to unhandled_exceptions_count in Boost.Log and implements functionality similar to the same named C++17 standard function. Tests and docs are also included. One notable difference from std::uncaught_exceptions is that the return type is unsigned rather than signed. This is deliberate as uncaught_exceptions must never return a negative value and unsigned int better documents that. Theoretically, as a counter, it may also overflow.
53 lines
1.5 KiB
Plaintext
53 lines
1.5 KiB
Plaintext
[/
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/ Copyright (c) 2018 Andrey Semashev
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/
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/ Distributed under the Boost Software License, Version 1.0. (See accompanying
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/ file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
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/]
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[section:uncaught_exceptions uncaught_exceptions]
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[simplesect Authors]
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* Andrey Semashev
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[endsimplesect]
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[section Header <boost/core/uncaught_exceptions.hpp>]
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The header `<boost/core/uncaught_exceptions.hpp>` defines the `boost::core::uncaught_exceptions` function,
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which is a more portable implementation of the same named function introduced in C++17. The function
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returns the number of the currently pending exceptions. When that function returns a value greater than 0,
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throwing an exception from a destructor can terminate the program.
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Unfortunately, the function cannot be implemented on every pre-C++17 compiler, although the most commonly
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used compilers are supported. When the compiler does not provide the necessary functionality,
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`boost::core::uncaught_exceptions` returns a non-zero value if at least one exception is pending (i.e. not
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necessarily the number of pending exceptions), and `BOOST_CORE_UNCAUGHT_EXCEPTIONS_EMULATED` macro
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is defined.
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[section Example]
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``
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class my_class
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{
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private:
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const unsigned int m_exception_count;
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public:
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my_class() : m_exception_count(boost::core::uncaught_exceptions())
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{
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}
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~my_class() noexcept(false)
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{
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if (m_exception_count == boost::core::uncaught_exceptions())
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do_something_potentially_throwing();
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}
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};
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``
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[endsect]
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[endsect]
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[endsect]
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