Difference between revisions of "cpp/memory/new/bad array new length"
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Andreas Krug (Talk | contribs) m (std::bad_array_new_length &e -> std::bad_array_new_length& e) |
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{{cpp/title|bad_array_new_length}} | {{cpp/title|bad_array_new_length}} | ||
| − | {{cpp/memory/new | + | {{cpp/memory/new/navbar}} |
{{dcl begin}} | {{dcl begin}} | ||
| − | {{dcl header | new}} | + | {{dcl header|new}} |
| − | {{dcl | since=c++11 | 1= | + | {{dcl|since=c++11|1= |
class bad_array_new_length; | class bad_array_new_length; | ||
}} | }} | ||
| Line 10: | Line 10: | ||
{{tt|std::bad_array_new_length}} is the type of the object thrown as exceptions by the [[cpp/language/new|new-expressions]] to report invalid array lengths if | {{tt|std::bad_array_new_length}} is the type of the object thrown as exceptions by the [[cpp/language/new|new-expressions]] to report invalid array lengths if | ||
| − | + | # Array length is negative, | |
| − | + | # Total size of the new array would exceed implementation-defined maximum value, | |
| − | + | # The number of initializer-clauses exceeds the number of elements to initialize. | |
| − | + | ||
| − | + | ||
Only the first array dimension may generate this exception; dimensions other than the first are constant expressions and are checked at compile time. | Only the first array dimension may generate this exception; dimensions other than the first are constant expressions and are checked at compile time. | ||
| Line 21: | Line 19: | ||
===Member functions=== | ===Member functions=== | ||
| − | {{ | + | {{cpp/error/exception/member of derived|bad_array_new_length|std=c++11}} |
| − | + | ||
| − | + | ||
{{cpp/memory/new/bad_alloc/inherit}} | {{cpp/memory/new/bad_alloc/inherit}} | ||
| + | |||
{{cpp/error/exception/inherit}} | {{cpp/error/exception/inherit}} | ||
| − | |||
| − | |||
| − | |||
===Example=== | ===Example=== | ||
{{example | {{example | ||
| − | + | |Three conditions where {{tt|std::bad_array_new_length}} should be thrown: | |
| − | + | |code= | |
| + | #include <climits> | ||
#include <iostream> | #include <iostream> | ||
#include <new> | #include <new> | ||
| − | |||
int main() | int main() | ||
{ | { | ||
| − | + | try | |
| − | + | { | |
| − | + | int negative = -1; | |
| − | + | new int[negative]; | |
| − | + | ||
| − | + | ||
| − | new int[ | + | |
| − | + | ||
| − | + | ||
} | } | ||
| + | catch (const std::bad_array_new_length& e) | ||
| + | { | ||
| + | std::cout << "1) " << e.what() << ": negative size\n"; | ||
| + | } | ||
| + | |||
| + | try | ||
| + | { | ||
| + | int small = 1; | ||
| + | new int[small]{1,2,3}; | ||
| + | } | ||
| + | catch (const std::bad_array_new_length& e) | ||
| + | { | ||
| + | std::cout << "2) " << e.what() << ": too many initializers\n"; | ||
| + | } | ||
| + | |||
| + | try | ||
| + | { | ||
| + | long large = LONG_MAX; | ||
| + | new int[large][1000]; | ||
| + | } | ||
| + | catch (const std::bad_array_new_length& e) | ||
| + | { | ||
| + | std::cout << "3) " << e.what() << ": too large\n"; | ||
| + | } | ||
| + | |||
| + | std::cout << "End\n"; | ||
} | } | ||
| + | |p=true | ||
| + | |output= | ||
| + | 1) std::bad_array_new_length: negative size | ||
| + | 2) std::bad_array_new_length: too many initializers | ||
| + | 3) std::bad_array_new_length: too large | ||
| + | End | ||
}} | }} | ||
===See also=== | ===See also=== | ||
{{dsc begin}} | {{dsc begin}} | ||
| − | {{dsc inc | cpp/memory/new/dsc operator_new}} | + | {{dsc inc|cpp/memory/new/dsc operator_new}} |
| − | {{dsc inc | cpp/memory/new/dsc bad_alloc}} | + | {{dsc inc|cpp/memory/new/dsc bad_alloc}} |
{{dsc end}} | {{dsc end}} | ||
{{langlinks|de|es|fr|it|ja|pt|ru|zh}} | {{langlinks|de|es|fr|it|ja|pt|ru|zh}} | ||
Latest revision as of 00:29, 6 January 2024
| Defined in header <new>
|
||
| class bad_array_new_length; |
(since C++11) | |
std::bad_array_new_length is the type of the object thrown as exceptions by the new-expressions to report invalid array lengths if
- Array length is negative,
- Total size of the new array would exceed implementation-defined maximum value,
- The number of initializer-clauses exceeds the number of elements to initialize.
Only the first array dimension may generate this exception; dimensions other than the first are constant expressions and are checked at compile time.
Inheritance diagram
Contents |
[edit] Member functions
| (constructor) |
constructs a new bad_array_new_length object (public member function) |
| operator= |
replaces the bad_array_new_length object (public member function) |
| what |
returns the explanatory string (public member function) |
std::bad_array_new_length::bad_array_new_length
| bad_array_new_length() noexcept; |
(1) | (since C++11) |
| bad_array_new_length( const bad_array_new_length& other ) noexcept; |
(2) | (since C++11) |
Constructs a new bad_array_new_length object with an implementation-defined null-terminated byte string which is accessible through what().
1) Default constructor.
2) Copy constructor. If *this and other both have dynamic type
std::bad_array_new_length then std::strcmp(what(), other.what()) == 0.Parameters
| other | - | another exception object to copy |
std::bad_array_new_length::operator=
| bad_array_new_length& operator=( const bad_array_new_length& other ) noexcept; |
(since C++11) | |
Assigns the contents with those of other. If *this and other both have dynamic type std::bad_array_new_length then std::strcmp(what(), other.what()) == 0 after assignment.
Parameters
| other | - | another exception object to assign with |
Return value
*this
std::bad_array_new_length::what
| virtual const char* what() const noexcept; |
(since C++11) | |
Returns the explanatory string.
Parameters
(none)
Return value
Pointer to a null-terminated string with explanatory information. The string is suitable for conversion and display as a std::wstring. The pointer is guaranteed to be valid at least until the exception object from which it is obtained is destroyed, or until a non-const member function (e.g. copy assignment operator) on the exception object is called.
Notes
Implementations are allowed but not required to override what().
Inherited from std::bad_alloc
Inherited from std::exception
Member functions
| [virtual] |
destroys the exception object (virtual public member function of std::exception)
|
| [virtual] |
returns an explanatory string (virtual public member function of std::exception)
|
[edit] Example
Three conditions where std::bad_array_new_length should be thrown:
Run this code
#include <climits> #include <iostream> #include <new> int main() { try { int negative = -1; new int[negative]; } catch (const std::bad_array_new_length& e) { std::cout << "1) " << e.what() << ": negative size\n"; } try { int small = 1; new int[small]{1,2,3}; } catch (const std::bad_array_new_length& e) { std::cout << "2) " << e.what() << ": too many initializers\n"; } try { long large = LONG_MAX; new int[large][1000]; } catch (const std::bad_array_new_length& e) { std::cout << "3) " << e.what() << ": too large\n"; } std::cout << "End\n"; }
Possible output:
1) std::bad_array_new_length: negative size 2) std::bad_array_new_length: too many initializers 3) std::bad_array_new_length: too large End
[edit] See also
| allocation functions (function) | |
| exception thrown when memory allocation fails (class) |
