arene::base::null_terminated_string_view Class Reference

A read-only string-view that provides a view onto a null-terminated string. More...

Inheritance diagram for arene::base::null_terminated_string_view:

Public Types
using	const_iterator = ::arene::base::detail::wrapped_iterator<const_pointer, passkey>
	The type of const iterator used by this view.
using	const_pointer = value_type const*
	The const pointer type of this view.
using	const_reference = value_type const&
	The type of a reference to an element in the view.
using	difference_type = typename iterator::difference_type
	The type used for differences between iterators in this view.
using	iterator = const_iterator
	The type of iterator used by this view.
using	pointer = value_type*
	The pointer type of this view.
using	reference = value_type&
	The type of a reference to an element in the view.
using	size_type = std::size_t
	The type used for sizes in this view.
using	value_type = detail::character
	The value type of this view.

Public Member Functions
constexpr	null_terminated_string_view () noexcept
	construct an empty string-view.
constexpr	null_terminated_string_view (detail::raw_c_string const string) noexcept
	construct a view on an existing null-terminated string.
constexpr	null_terminated_string_view (null_terminated_string_view &&)=default
	default move constructor
constexpr	null_terminated_string_view (null_terminated_string_view const &)=default
	default copy constructor
	null_terminated_string_view (std::nullptr_t)=delete
	constructing from a nullptr literal is always an error.
template<typename String, constraints< std::enable_if_t< std::is_same< String, std::string >::value > > = nullptr>
	null_terminated_string_view (String const &string) noexcept
	Implicit construction from a std::string (which is required to be null-terminated).
	~null_terminated_string_view ()=default
	default destructor
ARENE_NODISCARD constexpr auto	begin () const noexcept -> const_iterator
	Get an iterator to the first element of the string.
ARENE_NODISCARD constexpr auto	c_str () const noexcept -> const_pointer
	Obtain a C-style null-terminated string pointer.
constexpr auto	compare (null_terminated_string_view const other) const noexcept -> integral_comparison_result
	Compare this null-terminated string to another null-terminated string.
template<typename String, constraints< std::enable_if_t< std::is_same< String, std::string >::value > > = nullptr>
auto	compare (String const &other) const noexcept -> integral_comparison_result
	Compare this null-terminated string to a std::string.
constexpr auto	compare (string_view const &other) const noexcept -> integral_comparison_result
	Compare this null-terminated string to a string_view.
ARENE_NODISCARD constexpr auto	data () const noexcept -> const_pointer
	Obtain a C-style null-terminated string pointer.
ARENE_NODISCARD constexpr auto	empty () const noexcept -> bool
	Query if this string is the empty string.
ARENE_NODISCARD constexpr auto	length () const noexcept -> size_type
	Query the length of the string.
constexpr	operator string_view () const noexcept
	Implicit conversion to string_view.
constexpr auto	operator= (null_terminated_string_view &&) -> null_terminated_string_view &=default
	default move assignment
constexpr auto	operator= (null_terminated_string_view const &) -> null_terminated_string_view &=default
	default copy assignment
ARENE_NODISCARD constexpr auto	size () const noexcept -> size_type
	Query the length of the string.
ARENE_NODISCARD constexpr auto	substr (std::size_t offset) const noexcept -> null_terminated_string_view
	Compute the sub-string starting at the specified offset within the string.
ARENE_NODISCARD constexpr auto	substr (std::size_t offset, std::size_t max_length) const noexcept -> string_view
	Compute the sub-string starting at the specified offset and with the specified maximum length.

Static Public Member Functions
static ARENE_NODISCARD constexpr auto	end () noexcept -> sentinel
	Get the sentinel (end-iterator) of this string.
static constexpr auto	three_way_compare (null_terminated_string_view const lhs, detail::raw_c_string const rhs) noexcept -> strong_ordering
	Compare two null-terminated strings.
static constexpr auto	three_way_compare (null_terminated_string_view const lhs, null_terminated_string_view const rhs) noexcept -> strong_ordering
	Compare two null-terminated strings.
template<typename String, constraints< std::enable_if_t< std::is_same< String, std::string >::value > > = nullptr>
static auto	three_way_compare (null_terminated_string_view const lhs, String const &rhs) noexcept -> strong_ordering
	Compare a null-terminated string to a std::string.
static constexpr auto	three_way_compare (null_terminated_string_view const lhs, string_view const rhs) noexcept -> strong_ordering
	Compare a null-terminated string to a string_view.

Friends
ARENE_NODISCARD friend constexpr auto	operator!= (iterator const iter, sentinel) noexcept -> bool
	Equality comparison for a null terminated string view's iterator and the end-of-string sentinel.
ARENE_NODISCARD friend constexpr auto	operator== (iterator const iter, sentinel) noexcept -> bool
	Equality comparison for a null terminated string view's iterator and the end-of-string sentinel.

Detailed Description

A read-only string-view that provides a view onto a null-terminated string.

This string type can be used to pass around null-terminated strings more safely and explicitly compared to passing a 'const char*', making it easier to query the length of the string, compare strings, compute sub-strings, etc.

This class just holds a reference to a string stored elsewhere. The null_terminated_string_view does not own the elements of the string.

You should prefer to use string_view over this class unless the extra storage of the size_t required by string_view is prohibitively expensive compared to the cost of repeatedly calculating the string length every time it is used.

Member Typedef Documentation

const_iterator

using arene::base::null_terminated_string_view::const_iterator = ::arene::base::detail::wrapped_iterator<const_pointer, passkey>

The type of const iterator used by this view.

const_pointer

using arene::base::null_terminated_string_view::const_pointer = value_type const*

The const pointer type of this view.

const_reference

using arene::base::null_terminated_string_view::const_reference = value_type const&

The type of a reference to an element in the view.

difference_type

using arene::base::null_terminated_string_view::difference_type = typename iterator::difference_type

The type used for differences between iterators in this view.

iterator

using arene::base::null_terminated_string_view::iterator = const_iterator

The type of iterator used by this view.

pointer

using arene::base::null_terminated_string_view::pointer = value_type*

The pointer type of this view.

reference

using arene::base::null_terminated_string_view::reference = value_type&

The type of a reference to an element in the view.

size_type

using arene::base::null_terminated_string_view::size_type = std::size_t

The type used for sizes in this view.

value_type

using arene::base::null_terminated_string_view::value_type = detail::character

The value type of this view.

Constructor & Destructor Documentation

null_terminated_string_view() [1/6]

arene::base::null_terminated_string_view::null_terminated_string_view ( )

inlineconstexprnoexcept

construct an empty string-view.

null_terminated_string_view() [2/6]

arene::base::null_terminated_string_view::null_terminated_string_view ( null_terminated_string_view const & )

constexprdefault

default copy constructor

null_terminated_string_view() [3/6]

arene::base::null_terminated_string_view::null_terminated_string_view ( null_terminated_string_view && )

constexprdefault

default move constructor

~null_terminated_string_view()

arene::base::null_terminated_string_view::~null_terminated_string_view ( )

default

default destructor

null_terminated_string_view() [4/6]

arene::base::null_terminated_string_view::null_terminated_string_view ( std::nullptr_t )

explicitdelete

constructing from a nullptr literal is always an error.

null_terminated_string_view() [5/6]

arene::base::null_terminated_string_view::null_terminated_string_view ( detail::raw_c_string const string )

inlineexplicitconstexprnoexcept

construct a view on an existing null-terminated string.

Parameters

string

A pointer to the first character of the null-terminated string. Caller must ensure that the string is properly null-terminated. Passing a nullptr has undefined behaviour.

null_terminated_string_view() [6/6]

template<typename String, constraints< std::enable_if_t< std::is_same< String, std::string >::value > > = nullptr>

arene::base::null_terminated_string_view::null_terminated_string_view ( String const & string )

inlinenoexcept

Implicit construction from a std::string (which is required to be null-terminated).

The resulting string view is invalidated by any operation that modifies the string.

Parameters

string

The source string

Note

This constructor is a template rather than a non-template taking a const std::string& to avoid the possibility of unknowingly constructing a temporary std::string implicitly by passing something that is convertible to std::string. e.g. a std::initializer_list<char>

Member Function Documentation

begin()

ARENE_NODISCARD constexpr auto arene::base::null_terminated_string_view::begin ( ) const -> const_iterator

inlineconstexprnoexcept

Get an iterator to the first element of the string.

Returns

const_iterator An iterator to the first character in the string.

c_str()

ARENE_NODISCARD constexpr auto arene::base::null_terminated_string_view::c_str ( ) const -> const_pointer

inlineconstexprnoexcept

Obtain a C-style null-terminated string pointer.

Returns

const_pointer A pointer to the first character in the string.

compare() [1/3]

auto arene::base::null_terminated_string_view::compare ( null_terminated_string_view const other ) const -> integral_comparison_result

inlineconstexprnoexcept

Compare this null-terminated string to another null-terminated string.

Parameters

other

The other string to compare *this to.

Returns

integral_comparison_result A negative value if *this lexicographically precedes other, a positive value if other lexicographically precedes *this, or zero if the two strings are equal.

compare() [2/3]

template<typename String, constraints< std::enable_if_t< std::is_same< String, std::string >::value > > = nullptr>

auto arene::base::null_terminated_string_view::compare ( String const & other ) const -> integral_comparison_result

inlinenoexcept

Compare this null-terminated string to a std::string.

Parameters

other

The other string to compare *this to.

Returns

A negative value if *this lexicographically precedes other, a positive value if other lexicographically precedes *this, or zero if the two strings are equal.

Note

This constructor is a template rather than a non-template taking a const std::string& to handle when std::string is only declared, not defined.

compare() [3/3]

auto arene::base::null_terminated_string_view::compare ( string_view const & other ) const -> integral_comparison_result

inlineconstexprnoexcept

Compare this null-terminated string to a string_view.

Parameters

other

The other string to compare *this to.

Returns

A negative value if *this lexicographically precedes other, a positive value if other lexicographically precedes *this, or zero if the two strings are equal.

data()

ARENE_NODISCARD constexpr auto arene::base::null_terminated_string_view::data ( ) const -> const_pointer

inlineconstexprnoexcept

Obtain a C-style null-terminated string pointer.

Returns

const_pointer A pointer to the first character in the string.

empty()

ARENE_NODISCARD constexpr auto arene::base::null_terminated_string_view::empty ( ) const -> bool

inlineconstexprnoexcept

Query if this string is the empty string.

Returns

true if the string is empty, false otherwise

end()

static ARENE_NODISCARD constexpr auto arene::base::null_terminated_string_view::end ( ) -> sentinel

inlinestaticconstexprnoexcept

Get the sentinel (end-iterator) of this string.

Returns

sentinel The sentinel comparable to an iterator to mark the end of the string.

length()

ARENE_NODISCARD constexpr auto arene::base::null_terminated_string_view::length ( ) const -> size_type

inlineconstexprnoexcept

Query the length of the string.

Returns

The number of 'char' elements in the null-terminate string, not including the null-terminator.

Note

This operation needs to traverse the string to determine the length and so may be expensive to call repeatedly. If you need to call length() repeatedly then either cache the value or convert this object to a string_view first and use that instead.

operator string_view()

arene::base::null_terminated_string_view::operator string_view ( ) const

inlineconstexprnoexcept

Implicit conversion to string_view.

Returns

A string_view that spans the characters of *this, minus the null-terminator.

operator=() [1/2]

auto arene::base::null_terminated_string_view::operator= ( null_terminated_string_view && ) -> null_terminated_string_view &=default

constexprdefault

default move assignment

operator=() [2/2]

auto arene::base::null_terminated_string_view::operator= ( null_terminated_string_view const & ) -> null_terminated_string_view &=default

constexprdefault

default copy assignment

size()

ARENE_NODISCARD constexpr auto arene::base::null_terminated_string_view::size ( ) const -> size_type

inlineconstexprnoexcept

Query the length of the string.

Returns

The number of 'char' elements in the null-terminate string, not including the null-terminator.

Note

This operation needs to traverse the string to determine the length and so may be expensive to call repeatedly. If you need to call size() repeatedly then either cache the value or convert this object to a string_view first and use that instead.

substr() [1/2]

ARENE_NODISCARD constexpr auto arene::base::null_terminated_string_view::substr ( std::size_t offset ) const -> null_terminated_string_view

inlineconstexprnoexcept

Compute the sub-string starting at the specified offset within the string.

Parameters

offset

The index of the first character that the returned substring should start at.

Returns

null_terminated_string_view A view which starts at the character at index offset and continues to the end of the string. If offset is larger than length() then returns the empty string view.

Note

This operation has complexity of O(min(offset, length())).

substr() [2/2]

ARENE_NODISCARD constexpr auto arene::base::null_terminated_string_view::substr ( std::size_t offset, std::size_t max_length ) const -> string_view

inlineconstexprnoexcept

Compute the sub-string starting at the specified offset and with the specified maximum length.

Parameters

offset	The index of the first charcter of the substring. If this value is greater than length() then returns the empty sub-string.
max_length	The maximum length of the returned substring. The returned substring may be shorter than this length if there are fewer than max_length elements after offset.

Returns

string_view A substring referencing the elements of *this starting at index offset with a length at most max_length.

Note

This operation has complexity of O(min(offset+max_length, length()))

three_way_compare() [1/4]

static constexpr auto arene::base::null_terminated_string_view::three_way_compare ( null_terminated_string_view const lhs, detail::raw_c_string const rhs ) -> strong_ordering

inlinestaticconstexprnoexcept

Compare two null-terminated strings.

Parameters

lhs	The first string to compare
rhs	The second string to compare

Returns

strong_ordering::less if lhs lexicographically precedes rhs

strong_ordering::greater if rhs lexicographically precedes lhs

strong_ordering::equal if the two strings are equal.

three_way_compare() [2/4]

static constexpr auto arene::base::null_terminated_string_view::three_way_compare ( null_terminated_string_view const lhs, null_terminated_string_view const rhs ) -> strong_ordering

inlinestaticconstexprnoexcept

Compare two null-terminated strings.

Parameters

lhs	The first string to compare
rhs	The second string to compare

Returns

strong_ordering::less if lhs lexicographically precedes rhs

strong_ordering::greater if rhs lexicographically precedes lhs

strong_ordering::equal if the two strings are equal.

three_way_compare() [3/4]

template<typename String, constraints< std::enable_if_t< std::is_same< String, std::string >::value > > = nullptr>

static auto arene::base::null_terminated_string_view::three_way_compare ( null_terminated_string_view const lhs, String const & rhs ) -> strong_ordering

inlinestaticnoexcept

Compare a null-terminated string to a std::string.

Parameters

lhs	The first string to compare
rhs	The second string to compare

Returns

strong_ordering::less if lhs lexicographically precedes rhs

strong_ordering::greater if rhs lexicographically precedes lhs

strong_ordering::equal if the two strings are equal.

Note

This constructor is a template rather than a non-template taking a const std::string& to handle when std::string is only declared, not defined.

three_way_compare() [4/4]

static constexpr auto arene::base::null_terminated_string_view::three_way_compare ( null_terminated_string_view const lhs, string_view const rhs ) -> strong_ordering

inlinestaticconstexprnoexcept

Compare a null-terminated string to a string_view.

Parameters

lhs	The first string to compare
rhs	The second string to compare

Returns

strong_ordering::less if lhs lexicographically precedes rhs

strong_ordering::greater if rhs lexicographically precedes lhs

strong_ordering::equal if the two strings are equal.

Friends And Related Symbol Documentation

operator!=

ARENE_NODISCARD friend constexpr auto operator!= ( iterator const iter, sentinel  ) -> bool

friend

Equality comparison for a null terminated string view's iterator and the end-of-string sentinel.

Parameters

iter	The iterator to compare against the sentinel.

Returns

true if the iterator points to a '\0' character.

false Otherwise.

operator==

ARENE_NODISCARD friend constexpr auto operator== ( iterator const iter, sentinel  ) -> bool

friend

Equality comparison for a null terminated string view's iterator and the end-of-string sentinel.

Parameters

iter	The iterator to compare against the sentinel.

Returns

true if the iterator points to a '\0' character.

false Otherwise.

---

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

• arene/base/strings/null_terminated_string_view.hpp