5.5 KiB
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| array_wrapper |
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Header: array_wrapper.h
Since: All versions
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This class implements a zero cost C++ interface around a const or non-const C array. It presents the same API as std::array. It allows legacy C data to be more easily integrated with C++ interfaces and be accessed in a less error prone fashion. If C++11 or above is supported then most functions can be 'constexpr'.
Member types
value_type
size_type
difference_type
reference
value_type
reference
const_reference
pointer
const_pointer
iterator
const_iterator
reverse_iterator
const_reverse_iterator
Member constants
May be used as indexes in to the array.
SIZE = Size of the array
MAX_SIZE = SIZE
FRONT = 0
BACK = SIZE - 1
BEGIN = 0
END = SIZE
RBEGIN = SIZE - 1
REND = -1
Element access
T& at(size_t i)
ETL_CONSTEXPR const T& at(size_t i) const
Description
Returns a reference or const reference to the indexed element.
Emits an etl::array_wrapper_bounds if the index isout of range of the array.
If asserts or exceptions are not enabled then undefined behaviour occurs.
T& operator[](size_t i)
ETL_CONSTEXPR const T& operator[](size_t i) const
Description
Returns a reference or const reference to the indexed element.if the index is out of range of the array then undefined behaviour occurs.---
T& front()
ETL_CONSTEXPR const T& front() const
Description
Returns a reference or const reference to the first element.---
T& back()
ETL_CONSTEXPR const T& back() const
Description
Returns a reference or const reference to the last element.---
T* data()
ETL_CONSTEXPR const T* data() const
Description
Returns a pointer or const pointer to the array.---Modifiers
void fill(parameter_t value)
Description
Fill a non-cost array with the value.---
template <typename T, T(&ARRAYOTHER)[SIZE_]>
void swap(etl::array_wrapper<T, SIZE_, ARRAYOTHER>& other)
Description
Swaps the array contents with another.---Iterators
ETL_CONSTEXPR iterator begin()
ETL_CONSTEXPR const_iterator begin() constETL_CONSTEXPR const_iterator cbegin() const
Description
Returns an iterator to the beginning of the array.---
ETL_CONSTEXPR iterator end()
ETL_CONSTEXPR const_iterator end() constETL_CONSTEXPR const_iterator cend() const
Description
Returns an iterator to the end of the array.---
ETL_CONSTEXPR iterator rbegin()
ETL_CONSTEXPR const_reverse_iterator rbegin() const
ETL_CONSTEXPR const_reverse_iterator crbegin() const
Description
Returns a reverse iterator to the beginning of the array.---
ETL_CONSTEXPR iterator rend()
ETL_CONSTEXPR const_reverse_iterator rend() constETL_CONSTEXPR const_reverse_iterator crend() const
Description
Returns a reverse iterator to the end of the array.---Capacity
ETL_CONSTEXPR size_t size() const
Description
Returns the size of the view.---
ETL_CONSTEXPR size_t max_size() const
Description
Returns the maximum possible size of the view.---Non-member functions
Lexicographically comparisons
operator ==
Returns
true if the contents of the array views are equal, otherwise false.
operator !=
Returns
true if the contents of the array views are not equal, otherwise false.
operator <
Returns
true if the contents of the lhs are lexicographically less than the
contents of the rhs, otherwise false.
operator <=
Returns
true if the contents of the lhs are lexicographically less than or equal to the
contents of the rhs, otherwise false.
operator >
Returns
true if the contents of the lhs are lexicographically greater than the
contents of the rhs, otherwise false.
operator >=
Returns
true if the contents of the lhs are lexicographically greater than or equal to the
contents of the rhs, otherwise false
Swap
template <typename T, std::size_t SIZE, T(&ARRAYL)[SIZE], T(&ARRAYR)[SIZE]>
void swap(etl::array_wrapper<T, SIZE, ARRAYL>& lhs,
etl::array_wrapper<T, SIZE, ARRAYR>& rhs)
Description
Swaps the array contents of two arrays.
Hash
There is a specialisation for etl::hash for array_wrapper.
Macros
A macro is defined to ease the use of the class.
ETL_ARRAY_WRAPPER(type, array);
Example
// The address of the array MUST be deducible at compile time.
int cdata = { 1, 2, 3, 4, 5, 6, 7, 8, 9, 10 };
typedef ETL_ARRAY_WRAPPER(int, cdata) Data;
// All instances of 'Data' access the SAME array.Data data;
void Print(Data data)
{
Data::const_iterator itr = data.begin();
while (itr != data.end())
{
std::cout << *itr++ << " ";
}
}
Print(data); // Prints "1 2 3 4 5 6 7 8 9 10"
size_t hashvalue = etl::hash<Data>()(data);
// Using indexes
int firstElement = data[Data::FRONT];
int lastElement = data[Data::BACK];
// Using forward indexes
for (int i = Data::BEGIN; i < Data::END; ++i)
{
std::cout << data[i] << " ";
}
// Using reverse indexes
for (int i = Data::RBEGIN; i < Data::REND; --i)
{
std::cout << data[i] << " ";
}