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* Add ranges * Initial Hugo setup * Work in progress * Added selection for local or remote site * Updated to 'light' theme * Changed to using Hextra Hugo theme * Changed to using Hextra Hugo theme * Changed to Hextra Hugo theme * Change to Hextra Hugo theme * Updated Hugo setup. * Updated Hugo setup. # Conflicts: # docs/releases/_index.md * Work in progress * Added new fonts Added new documentation * Latest documentation updates * Latest documentation updates # Conflicts: # docs/containers/array.md # docs/containers/array_view.md # docs/containers/array_wrapper.md # docs/containers/bip_buffer_spsc_atomic.md # docs/containers/bitset.md # docs/containers/indirect_vector.md # docs/containers/vector.md # docs/getting-started/compilers.md * Added bloom_filter markdown doc * Added more documentation Updated CSS for light and dark modes * Fixed some menus Added mode documentation files * Updated CSS rules Added badges to home page Added uniqur_ptr + pool tutorial * Fixed formatting on the home page markdown Modified light amd dark code formatting * Updated unique_ptr-with-pool * Added container and shared message tutorials * Updates to documentation * Added const_multimap * Updated source-formatting.md * Added initial raw text files form Web site editor * Innore coverage build directory * Exported raw text documentation files from the web site editor * Hugo updates * Added Hugo intalation and markdown descriptions * More addition to the documentation * Added closure.md and updates to delegate.md * Added format.md * Added documentation for etl::delegate_observable, etl::function, Base64 codec * Added io_port documentation * Added basic_format_spec * Added documentation for string_stream and string utilities. * Added more documentation Updated the documentation CSS * Added documentation for clocks, day, duration * Added more documentation for chrono classes Updated callouts * More chrono documentation * Completed chrono documentation * Maths functions documentation * Completed maths documentation * Completed maths documentation * Completed maths documentation * Completed maths documentation * Added multiple documentation files * Added iterator.md * Added debug_count.md and versions.md * Added debug_count.md and versions.md * Added more documentation * More documentation * Added some design pattern documentation Modified some of the layout files Modified the About documentation * Converted more documentation pages Modified the site CSS * Added more documentation Moced some documentation files to new directories * Added more documentation Tweaks to CSS * Added callback_timer_deferred_locked documentation * Added callback_timer_locked documentation * More documentation updates * More documentation updates * More documentation updates * New documentation files. Harmonised file name format * New documentation files. * Multiple document updates * Multiple document updates * Final conversion of web pages * Updates before PR * Updates before PR * Updates before PR # Conflicts: # docs/blog/_index.md * Final pre PR updates * Updates to message framework documentation * Renamed directory * Fix spelling * Added author and date to blog files Moved documentation files merged from development * Fixed 'Description' typo * Fix typos # Conflicts: # docs/IO/io_port.md # docs/containers/sets/const-multiset.md # docs/containers/sets/const-set.md # docs/maths/correlation.md # docs/maths/gamma.md * Renamed two files to lower case * Minor renaming * Added author and date * Updated callout on bresenham_line.md Added support for showing the ETL version on the documentation first page, by copying the version.txt file as a hugo asset. Updated the Python 'update_release.py' to copy 'version.txt' * Replace space in filename with hyphen. Added more information to hugo-commands.md * Replace space in filename with hyphen. Added more information to hugo-commands.md # Conflicts: # docs/getting-started/view-the-docs-locally/hugo-commands.md * Added a link to pseudo_moving_average.md * Updated title pages for groups * Fixed missing 404 for non-existent pages * Fixed coordinate variable names in the 'Calculating the intersection' example --------- Co-authored-by: Roland Reichwein <Roland.Reichwein@bmw.de> Co-authored-by: John Wellbelove <john.wellbelove@etlcpp.com> Co-authored-by: John Wellbelove <john.wellbelove@etlcpp.co.uk>
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| expected |
{{< callout type="info">}}
Header: expected.h
From: 20.35.13
Similar to: std::expected
{{< /callout >}}
A generic result type for returning either a result or an error.
Replacement for etl::result.
template <typename TValue, typename TError>
class expected
Specialisation for void result.
template <typename TError>
class expected<void, TError>
unexpected
template class unexpected
unexpect_t
A tag type for in-place construction of an unexpected value in an etl::expected object.
struct unexpect_t;
A constant of type etl::unexpect_t which is directly passed to a constructor of etl::expected to construct an unexpected value.
inline constexpr unexpect_t unexpect;
From: C++17.
static const unexpect_t unexpect;
Before: C++17.
unexpected
template <typename TError>
class unexpected<TError>
Types
error_type = TError
Member functions
ETL_CONSTEXPR
unexpected(const unexpected& other)
Description
Copy constructor
ETL_CONSTEXPR
unexpected(unexpected&& other)
Description
Move constructor.
Since: C++11
template <typename TError>
constexpr explicit unexpected(TError&& e)
Description
Construct from an argument.
Since: C++11
template <typename TError>
explicit unexpected(const TError& e)
Description
Construct from argument.
Before: C++11
template <typename... TArgs>
constexpr explicit unexpected(etl::in_place_t, TArgs&&... args)
Description
Construct from arguments.
Since: C++11
template <typename U, typename... TArgs>
constexpr explicit unexpected(etl::in_place_t, std::initializer_list<U> init, TArgs&&... args)
Description
Construct from initializer_list and arguments.
Since: C++11
ETL_CONSTEXPR14
etl::unexpected<TError>& operator =(const etl::unexpected<TError>& rhs)
Description
Assign from etl::unexpected
ETL_CONSTEXPR14
etl::unexpected<TError>& operator =(etl::unexpected<TError>&& rhs)
Description
Move assign from etl::unexpected
Since: C++11
TError& error() & noexcept
Description
Get the error.
Since: C++11
constexpr const TError& error() const& noexcept
Description
Get the error.
Since: C++11
TError&& error() && noexcept
Description
Get the error.
Since: C++11
constexpr TError&& error() const&& noexcept
Description
Get the error.
Since: C++11
const TError& error() const
Description
Get the error.
Before: C++11
void swap(etl::unexpected<TError>& other)
Description
Swap with another etl::unexpected
expected
template <typename TValue, typename TError>
class expected
```cpp
Specialisation for void value type.
```cpp
template <typename TError>
class expected<void, TError>
```cpp
### Types
```cpp
this_type etl::expected<TValue, TError>
value_type TValue
error_type TError
unexpected_type etl::unexpected<TError>
Member functions
ETL_CONSTEXPR14 expected() ETL_NOEXCEPT
Description
Default constructor
ETL_CONSTEXPR14 expected(const value_type& value) ETL_NOEXCEPT
Description
Constructor
ETL_CONSTEXPR14 expected(value_type&& value) ETL_NOEXCEPT
Description
Constructor
Since: C++11
ETL_CONSTEXPR14 expected(const expected& other) ETL_NOEXCEPT
Description
Copy constructor
ETL_CONSTEXPR14 expected(expected&& other) ETL_NOEXCEPT
Description
Move constructor
Since: C++11
template <typename F>
ETL_CONSTEXPR14 explicit expected(const etl::unexpected<F>& ue)
Description
Copy construct from unexpected type.
template <typename F>
ETL_CONSTEXPR14 explicit expected(etl::unexpected<F>&& ue)
Description
Move construct from unexpected type.
Since: C++11
ETL_CONSTEXPR14 explicit expected(etl::in_place_t) ETL_NOEXCEPT
Description
Construct with default value type.
template <typename... TArgs>
ETL_CONSTEXPR14 explicit expected(etl::in_place_t, TArgs&&... args)
Description
Construct value type from arguments.
Since: C++11
template <typename U, typename... TArgs>
ETL_CONSTEXPR14 explicit expected(etl::in_place_t, std::initializer_list<U> il, TArgs&&... args)
Description
Construct value type from initializer_list and arguments.
template <typename... TArgs>
ETL_CONSTEXPR14 explicit expected(etl::unexpect_t, TArgs&&... args)
Description
Construct error type from arguments.
Since: C++11
template <typename U, typename... TArgs>
ETL_CONSTEXPR14 explicit expected(etl::unexpect_t, std::initializer_list<U> il, TArgs&&... args)
Description
Construct error type from initializer_list and arguments.
Since: C++11
this_type& operator =(const this_type& other)
Description
Copy assign
this_type& operator =(this_type&& other)
Description
Move assign
Since: C++11
expected& operator =(const value_type& value)
Description
Copy assign from value
expected& operator =(value_type&& value)
Description
Move assign from value
Since: C++11
expected& operator =(const unexpected_type& error)
Description
Copy assign from error
expected& operator =(unexpected_type&& error)
Description
Move assign from error
Since: C++11
ETL_CONSTEXPR14 value_type& value()&
Description
Get the value.
Undefined if has_value() returns false.
Not valid for void specialisation.
Since: C++11
ETL_CONSTEXPR14 const value_type& value() const&
Description
Get the value.
Undefined if has_value() returns false.
Not valid for void specialisation.
Since: C++11
ETL_CONSTEXPR14 value_type&& value()&&
Description
Get the value.
Undefined if has_value() returns false.
Not valid for void specialisation.
Since: C++11
ETL_CONSTEXPR14 const value_type&& value() const&&
Description
Get the value.
Undefined if has_value() returns false.
Not valid for void specialisation.
Since: C++11
value_type& value() const
Description
Get the value.
Undefined if has_value() returns false.
Not valid for void specialisation.
ETL_NODISCARD
ETL_CONSTEXPR14
bool has_value() const
Description
Returns true if the class contains a value.
ETL_NODISCARD
ETL_CONSTEXPR14
operator bool() const
Description
Returns true if the class contains a value.
template <typename U>
ETL_NODISCARD
ETL_CONSTEXPR14
value_type value_or(U&& default_value) const&
Description
Returns the value or default_value if has_value() returns false.
Since: C++11
template <typename U>
ETL_NODISCARD
ETL_CONSTEXPR14
value_type value_or(U&& default_value)&&
Description
Returns the value or default_value if has_value() returns false.
Since: C++11
template <typename U>
value_type value_or(const U& default_value) const
Description
Returns the value or default_value if has_value() returns false.
Before: C++11
ETL_NODISCARD
ETL_CONSTEXPR14
error_type& error()& ETL_NOEXCEPT
Description
Returns the error.
Undefined if has_value() returns true.
Since: C++11
ETL_NODISCARD
ETL_CONSTEXPR14
const error_type& error() const& ETL_NOEXCEPT
Description
Returns the error.
Undefined if has_value() returns true.
Since: C++11
ETL_NODISCARD
ETL_CONSTEXPR14
error_type&& error() && ETL_NOEXCEPT
Description
Returns the error.
Undefined if has_value() returns true.
Since: C++11
ETL_NODISCARD
ETL_CONSTEXPR14
const error_type&& error() const&& ETL_NOEXCEPT
Description
Returns the error.
Undefined if has_value() returns true.
Since: C++11
error_type& error() const
Description
Returns the error.
Undefined if has_value() returns true.
Before: C++11
template <typename... TArgs>
ETL_CONSTEXPR14 value_type& emplace(TArgs&&... args) ETL_NOEXCEPT
Description
Returns the error if has_value() returns false.
Undefined if has_value() returns true.
Since: C++11
template <typename U, typename... TArgs>
ETL_CONSTEXPR14 value_type& emplace(std::initializer_list<U>& il, TArgs&&... args) ETL_NOEXCEPT
Description
Create from arguments.
Since: C++11
value_type* operator ->()
Description
Class member access operator.
const value_type* operator ->() const
Description
Const class member access operator.
value_type& operator *()
Description
Dereference operator.
const value_type& operator *() const
Description
Dereference operator.