Exiv2::Slice< container > Struct Template Reference

Slice (= view) for STL containers. More...

#include <slice.hpp>

Inheritance diagram for Exiv2::Slice< container >:

Public Types
typedef container::iterator	iterator
typedef container::const_iterator	const_iterator
typedef Internal::remove_cv< typename container::value_type >::type	value_type
Public Types inherited from Exiv2::Internal::MutableSliceBase< Internal::ContainerStorage, container >
typedef ConstSliceBase< Internal::ContainerStorage, container >::iterator	iterator
typedef ConstSliceBase< Internal::ContainerStorage, container >::const_iterator	const_iterator
typedef ConstSliceBase< Internal::ContainerStorage, container >::value_type	value_type
Public Types inherited from Exiv2::Internal::ConstSliceBase< Internal::ContainerStorage, container >
typedef Internal::ContainerStorage< container >::iterator	iterator
typedef Internal::ContainerStorage< container >::const_iterator	const_iterator
typedef Internal::ContainerStorage< container >::value_type	value_type

Public Member Functions
	Slice (container &cont, size_t begin, size_t end)
	Construct a slice of the container cont starting at begin (including) and ending before end. More...
Slice	subSlice (size_t begin, size_t end)
Slice< const container >	subSlice (size_t begin, size_t end) const
Public Member Functions inherited from Exiv2::Internal::MutableSliceBase< Internal::ContainerStorage, container >
	MutableSliceBase (container &data, size_t begin, size_t end)
value_type &	at (size_t index)
const value_type &	at (size_t index) const
iterator	begin () throw ()
iterator	end () throw ()
Public Member Functions inherited from Exiv2::Internal::ConstSliceBase< Internal::ContainerStorage, container >
	ConstSliceBase (container &data, size_t begin, size_t end)
const value_type &	at (size_t index) const
const_iterator	cbegin () const throw ()
const_iterator	cend () const throw ()
slice_type	subSlice (size_t begin, size_t end) const
Public Member Functions inherited from Exiv2::Internal::SliceBase
	SliceBase (size_t begin, size_t end)
size_t	size () const throw ()

Additional Inherited Members
Protected Types inherited from Exiv2::Internal::MutableSliceBase< Internal::ContainerStorage, container >
typedef ConstSliceBase< Internal::ContainerStorage, container >	base_type
Protected Member Functions inherited from Exiv2::Internal::MutableSliceBase< Internal::ContainerStorage, container >
ConstSliceBase< Internal::ContainerStorage, const container >	to_const_base () const throw ()
slice_type	subSlice (size_t begin, size_t end)
Protected Member Functions inherited from Exiv2::Internal::SliceBase
void	rangeCheck (size_t index) const
Protected Attributes inherited from Exiv2::Internal::ConstSliceBase< Internal::ContainerStorage, container >
Internal::ContainerStorage< container >	storage_
Protected Attributes inherited from Exiv2::Internal::SliceBase
const size_t	begin_
const size_t	end_

Detailed Description

template<typename container>
struct Exiv2::Slice< container >

Slice (= view) for STL containers.

This is a very simple implementation of slices (i.e. views of sub-arrays) for STL containers that support O(1) element access and random access iterators (like std::vector, std::array and std::string).

A slice represents the semi-open interval [begin, end) and provides a (mutable) view, it does however not own the data! It can be used to conveniently pass parts of containers into functions without having to use iterators or offsets.

In contrast to C++20's std::span<T> it is impossible to read beyond the container's bounds and unchecked access is not-possible (by design).

Example usage:

std::vector<int> vec = {0, 1, 2, 3, 4};
slice<std::vector<int> > one_two(vec, 1, 3);
assert(one_two.size() == 2);
assert(one_two.at(0) == 1 && one_two.at(1) == 2);
// mutate the contents:
one_two.at(0) *= 2;
one_two.at(1) *= 3;
assert(one_two.at(0) == 2 && one_two.at(1) == 6);

Slices also offer access via iterators of the same type as the underlying container, so that they can be used in a comparable fashion:

std::vector<int> vec = {0, 1, 2, 3, 4};
slice<std::vector<int>> three_four(vec, 3, 5);
assert(*three_four.begin() == 3 && *three_four.end() == 4);
// this prints:
// 3
// 4
for (const auto & elem : three_four) {
    std::cout << elem << std::endl;
}

Template Parameters

container

A STL container type, like vector or array. Must support array-like access via the at() method.

Constructor & Destructor Documentation

Slice()

template<typename container >

Exiv2::Slice< container >::Slice ( container &  cont, size_t  begin, size_t  end  )

inline

Construct a slice of the container cont starting at begin (including) and ending before end.

Parameters

[in]	cont	Reference to the container
[in]	begin	First element of the slice.
[in]	end	First element beyond the slice.

Exceptions

std::out_of_range

For invalid slice bounds: when end is not larger than begin or when the slice's bounds are larger than the container's size.

Please note that due to the requirement that end must be larger than begin (they cannot be equal) it is impossible to construct a slice with zero length.

Member Function Documentation

subSlice() [1/2]

template<typename container >

Slice Exiv2::Slice< container >::subSlice ( size_t  begin, size_t  end  )

inline

Construct a sub-slice of this slice with the given bounds. The bounds are evaluated with respect to the current slice.

Parameters

[in]	begin	First element in the new slice.
[in]	end	First element beyond the new slice.

Exceptions

std::out_of_range

when begin or end are invalid

References Exiv2::Internal::MutableSliceBase< Internal::ContainerStorage, container >::begin(), and Exiv2::Internal::MutableSliceBase< Internal::ContainerStorage, container >::end().

subSlice() [2/2]

template<typename container >

Slice<const container> Exiv2::Slice< container >::subSlice ( size_t  begin, size_t  end  ) const

inline

Constructs a new constant subSlice. Behaves otherwise exactly like the non-const version.

References Exiv2::Internal::MutableSliceBase< Internal::ContainerStorage, container >::begin(), Exiv2::Internal::MutableSliceBase< Internal::ContainerStorage, container >::end(), and Exiv2::Internal::MutableSliceBase< Internal::ContainerStorage, container >::to_const_base().

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The documentation for this struct was generated from the following file:

• slice.hpp