tmp/tmpwm5yqqwi/{from.md → to.md}
RENAMED
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@@ -62,36 +62,60 @@ The handlers for a try block are tried in order of appearance.
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[*Note 2*: This makes it possible to write handlers that can never be
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executed, for example by placing a handler for a final derived class
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after a handler for a corresponding unambiguous public base
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class. — *end note*]
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A `...` in a handler’s *exception-declaration*
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`...` in a function parameter declaration; it specifies a match for any
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exception. If present, a `...` handler shall be the last handler for its
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try block.
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If no match is found among the handlers for a try block, the search for
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a matching handler continues in a dynamically surrounding try block of
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the same thread.
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A handler is considered *active* when initialization is complete for the
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parameter (if any) of the catch clause.
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[*Note
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point. — *end note*]
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Also, an implicit handler is considered active when the function
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`std::terminate` is entered due to a throw. A handler is no longer
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considered active when the catch clause exits.
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The exception with the most recently activated handler that is still
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active is called the *currently handled exception*.
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If no matching handler is found, the function `std::terminate` is
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invoked; whether or not the stack is unwound before this invocation of
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`std::terminate` is *implementation-defined* [[except.terminate]].
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Referring to any non-static member or base class of an object in the
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handler for a *function-try-block* of a constructor or destructor for
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that object results in undefined behavior.
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Exceptions thrown in destructors of objects with static storage duration
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@@ -123,10 +147,10 @@ follows:
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The lifetime of the variable ends when the handler exits, after the
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destruction of any objects with automatic storage duration initialized
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within the handler.
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When the handler declares an object, any changes to that
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affect the exception object. When the handler declares a
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object, any changes to the referenced object are changes
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-
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[*Note 2*: This makes it possible to write handlers that can never be
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executed, for example by placing a handler for a final derived class
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after a handler for a corresponding unambiguous public base
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class. — *end note*]
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A `...` in a handler’s *exception-declaration* specifies a match for any
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exception. If present, a `...` handler shall be the last handler for its
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try block.
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If no match is found among the handlers for a try block, the search for
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a matching handler continues in a dynamically surrounding try block of
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the same thread.
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If the search for a handler exits the function body of a function with a
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non-throwing exception specification, the function `std::terminate`
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[[except.terminate]] is invoked.
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[*Note 3*: An implementation is not permitted to reject an expression
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merely because, when executed, it throws or might throw an exception
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from a function with a non-throwing exception
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specification. — *end note*]
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[*Example 2*:
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``` cpp
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extern void f(); // potentially-throwing
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void g() noexcept {
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f(); // valid, even if f throws
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throw 42; // valid, effectively a call to std::terminate
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}
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```
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The call to `f` is well-formed despite the possibility for it to throw
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an exception.
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— *end example*]
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If no matching handler is found, the function `std::terminate` is
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invoked; whether or not the stack is unwound before this invocation of
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`std::terminate` is *implementation-defined* [[except.terminate]].
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A handler is considered *active* when initialization is complete for the
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parameter (if any) of the catch clause.
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[*Note 4*: The stack will have been unwound at that
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point. — *end note*]
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Also, an implicit handler is considered active when the function
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`std::terminate` is entered due to a throw. A handler is no longer
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considered active when the catch clause exits.
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The exception with the most recently activated handler that is still
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active is called the *currently handled exception*.
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Referring to any non-static member or base class of an object in the
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handler for a *function-try-block* of a constructor or destructor for
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that object results in undefined behavior.
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Exceptions thrown in destructors of objects with static storage duration
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The lifetime of the variable ends when the handler exits, after the
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destruction of any objects with automatic storage duration initialized
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within the handler.
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[*Note 5*: When the handler declares an object, any changes to that
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object will not affect the exception object. When the handler declares a
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reference to an object, any changes to the referenced object are changes
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to the exception object. — *end note*]
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