Cogs::StringView Class Reference

Provides a weakly referenced view over the contents of a string. More...

#include <StringView.h>

Public Types
using	iterator = const char *
	Iterator type.
using	const_iterator = const char *
	Const iterator type.
using	value_type = char
	Value type.
using	Vector = Cogs::Collections::SmallVector< StringView, 10 >
	Vector of strings type.

Public Member Functions
constexpr	StringView () noexcept=default
	Constructs an empty string view.
constexpr	StringView (const char *data) noexcept
	Construct a string view of the given null-terminated string.
template<size_t LENGTH>
constexpr	StringView (const char(&data)[LENGTH]) noexcept
	Construct a string view from the given string literal.
constexpr	StringView (const char *data, const size_t length) noexcept
	Construct a string view of the given string data, with the given length.
constexpr	StringView (const std::string_view s) noexcept
	Construct a String view of the given std::string_view object.
	StringView (const std::string &s) noexcept
	Construct a string view of the given string object.
bool	operator== (const StringView &other) const
	Operator equal.
constexpr iterator	begin () noexcept
	Iterator to the beginning of the string.
constexpr iterator	end () noexcept
	Iterator to the end of the string.
constexpr const_iterator	begin () const noexcept
	Const iterator to the beginning of the string.
constexpr const_iterator	end () const noexcept
	Const iterator to the end of the string.
constexpr const_iterator	cbegin () const noexcept
	Const iterator to the beginning of the string.
constexpr const_iterator	cend () const noexcept
	Const iterator to the end of the string.
constexpr bool	empty () const noexcept
	Check if the string is empty.
constexpr	operator bool () const noexcept
	Explicit boolean conversion operator.
	operator std::string () const
	Explicit std::string conversion operator.
constexpr	operator std::string_view () const noexcept
	Implicit std::string_view conversion operator.
std::string	to_string () const
	String conversion method.
constexpr std::string_view	to_string_view () const noexcept
	Create a standard library string_view of the same view.
constexpr const char *	data () const noexcept
	Get the sequence of characters referenced by the string view.
constexpr size_t	size () const noexcept
	Get the size of the string.
constexpr size_t	length () const noexcept
	Get the length of the string.
constexpr char	operator[] (const size_t index) const noexcept
	Get the character at position index in the string.
constexpr size_t	hash () const noexcept
	Get the hash code of the string.
constexpr size_t	hash (size_t hashValue) const noexcept
	Combine the hash code of the string with the initial hash value provided.
size_t	hashLowercase (size_t hashValue=Cogs::hash()) const noexcept
	Get the hash code of the string converted to lowercase.
size_t	find (const StringView &other, size_t offset=0) const noexcept
	Find the given string segment inside the string.
size_t	find_first_of (char character, size_t pos=0) const noexcept
	Find the first occurance of the given character from the specified starting position.
size_t	find_last_of (const StringView characters, size_t pos=NoPosition) const noexcept
	See std::basic_string::find_last_of.
size_t	find_last_of (const char character, size_t pos=NoPosition) const noexcept
	See std::basic_string::find_last_of.
int	compare (const StringView &other) const noexcept
	Lexicographically compares the content of this string view with the given other.
constexpr StringView	substr (size_t offset, size_t count=NoPosition) const noexcept
	Get the given sub string.
Vector	split (const StringView &delimiters) const
	Split this string into parts.
Vector	splitAll (const StringView &delimiters) const
	Split this string into parts, empty parts will be retained.
StringView &	trimStart () noexcept
	Remove any whitespace from the start of this StringView's contents.
StringView &	trimEnd () noexcept
	Remove any whitespace from the end of this StringView's contents.
StringView &	trim () noexcept
	Remove any whitespace from the start and end of this StringView's contents.

Static Public Attributes
static constexpr size_t	npos = static_cast<size_t>(-1)
	No position.
static constexpr size_t	NoPosition = npos
	No position.

Private Types
using	traits_type = std::char_traits< char >

Private Member Functions
int	compareMemory (const char *a, const char *b, size_t length) const
	Compare two memory sequences.

Static Private Member Functions
static bool	isWhiteSpace (char c)
	Helper function that tests whether the given character is an ASCII whitespace character.

Private Attributes
const char *	str = nullptr
	Pointer to the string this view is over.
size_t	strSize = 0
	Length of the string data pointed to.

Detailed Description

Provides a weakly referenced view over the contents of a string.

E.g. same usage rules as std::string_view

No ownership is assumed over the given string, making the valid lifetime of a StringView bound to the lifetime of the string data it is constructed from. Therefore, it is usually not safe to store instances of StringView in objects, except when it can be reasonably guaranteed that the strings in question are literals or otherwise exists in the StringView instance usage lifetime.

Member Typedef Documentation

const_iterator

using Cogs::StringView::const_iterator = const char *

Const iterator type.

iterator

using Cogs::StringView::iterator = const char *

Iterator type.

traits_type

using Cogs::StringView::traits_type = std::char_traits<char>

private

value_type

using Cogs::StringView::value_type = char

Value type.

Vector

using Cogs::StringView::Vector = Cogs::Collections::SmallVector<StringView, 10>

Vector of strings type.

Constructor & Destructor Documentation

StringView() [1/6]

constexpr Cogs::StringView::StringView ( )

constexprdefaultnoexcept

Constructs an empty string view.

StringView() [2/6]

constexpr Cogs::StringView::StringView ( const char *  data )

inlineconstexprnoexcept

Construct a string view of the given null-terminated string.

The string length is automatically calculated from the string data.

Parameters

data	Pointer to string data in memory.

StringView() [3/6]

template<size_t LENGTH>

constexpr Cogs::StringView::StringView ( const char(&)  data[LENGTH] )

inlineconstexprnoexcept

Construct a string view from the given string literal.

Parameters

data	Pointer to the string literal.

StringView() [4/6]

constexpr Cogs::StringView::StringView ( const char *  data, const size_t  length  )

inlineconstexprnoexcept

Construct a string view of the given string data, with the given length.

Parameters

data	Pointer to string data in memory.
length	Length of the string data, not including null-termination, if any.

StringView() [5/6]

constexpr Cogs::StringView::StringView ( const std::string_view  s )

inlineconstexprnoexcept

Construct a String view of the given std::string_view object.

Parameters

s	string_view to create a view of.

StringView() [6/6]

Cogs::StringView::StringView ( const std::string &  s )

noexcept

Construct a string view of the given string object.

Parameters

s	String to create a view of.

Member Function Documentation

begin() [1/2]

constexpr const_iterator Cogs::StringView::begin ( ) const

inlineconstexprnoexcept

Const iterator to the beginning of the string.

begin() [2/2]

constexpr iterator Cogs::StringView::begin ( )

inlineconstexprnoexcept

Iterator to the beginning of the string.

cbegin()

constexpr const_iterator Cogs::StringView::cbegin ( ) const

inlineconstexprnoexcept

Const iterator to the beginning of the string.

cend()

constexpr const_iterator Cogs::StringView::cend ( ) const

inlineconstexprnoexcept

Const iterator to the end of the string.

compare()

int Cogs::StringView::compare ( const StringView &  other ) const

noexcept

Lexicographically compares the content of this string view with the given other.

Parameters

other

StringView instance to compare to.

Returns

An integer signaling the order of the strings. See std::basic_string::compare() docs for details.

compareMemory()

int Cogs::StringView::compareMemory ( const char *  a, const char *  b, size_t  length  ) const

inlineprivate

Compare two memory sequences.

data()

constexpr const char * Cogs::StringView::data ( ) const

inlineconstexprnoexcept

Get the sequence of characters referenced by the string view.

Note: the data is not necessarily null-terminated, and may even contain null characters. To get a null-terminated string, use to_string.

Returns

A pointer to the underlying sequence of characters.

Referenced by Cogs::ImmutableString::ImmutableString(), and Cogs::Memory::MemoryBuffer::writeString().

empty()

constexpr bool Cogs::StringView::empty ( ) const

inlineconstexprnoexcept

Check if the string is empty.

Returns

True if the string is empty (string length is zero).

Referenced by Cogs::Reflection::TypeDatabase::createType(), and Cogs::ImmutableString::ImmutableString().

end() [1/2]

constexpr const_iterator Cogs::StringView::end ( ) const

inlineconstexprnoexcept

Const iterator to the end of the string.

end() [2/2]

constexpr iterator Cogs::StringView::end ( )

inlineconstexprnoexcept

Iterator to the end of the string.

find()

size_t Cogs::StringView::find ( const StringView &  other, size_t  offset = 0  ) const

noexcept

Find the given string segment inside the string.

Starts the search at character offset.

Returns

Starting position of the found string, NoPosition if not found.

find_first_of()

size_t Cogs::StringView::find_first_of ( char  character, size_t  pos = 0  ) const

noexcept

Find the first occurance of the given character from the specified starting position.

Referenced by split(), and splitAll().

find_last_of() [1/2]

size_t Cogs::StringView::find_last_of ( const char  character, size_t  pos = NoPosition  ) const

noexcept

See std::basic_string::find_last_of.

References Cogs::N.

find_last_of() [2/2]

size_t Cogs::StringView::find_last_of ( const StringView  characters, size_t  pos = NoPosition  ) const

noexcept

See std::basic_string::find_last_of.

References Cogs::N.

hash() [1/2]

constexpr size_t Cogs::StringView::hash ( ) const

inlineconstexprnoexcept

Get the hash code of the string.

Returns

Hash code.

References Cogs::hash().

hash() [2/2]

constexpr size_t Cogs::StringView::hash ( size_t  hashValue ) const

inlineconstexprnoexcept

Combine the hash code of the string with the initial hash value provided.

Deprecated. Use Cogs::hash(string, hashValue)

Returns

Hash code.

References Cogs::hash().

hashLowercase()

size_t Cogs::StringView::hashLowercase ( size_t  hashValue = Cogs::hash() ) const

noexcept

Get the hash code of the string converted to lowercase.

Deprecated. Use Cogs::hashLowercase(string, hashValue)

Lowercase is here defined as default "C" locale, i.e., A-Z is converted to a-z.

Returns

Hash code.

References Cogs::hashLowercase().

isWhiteSpace()

static bool Cogs::StringView::isWhiteSpace ( char  c )

inlinestaticprivate

Helper function that tests whether the given character is an ASCII whitespace character.

Tests for tab (\t), line feed (
), carriage return (\r), and space ( ).

length()

constexpr size_t Cogs::StringView::length ( ) const

inlineconstexprnoexcept

Get the length of the string.

Equivalent to size().

Returns

Length of the string.

operator bool()

constexpr Cogs::StringView::operator bool ( ) const

inlineexplicitconstexprnoexcept

Explicit boolean conversion operator.

Provided for better check before use semantics.

Returns

True if the string is non-empty.

operator std::string()

Cogs::StringView::operator std::string ( ) const

inlineexplicit

Explicit std::string conversion operator.

Provided to make it possible to cast a string view to a std::string.

Returns

A std::string object with a copy of the string held by this StringView.

operator std::string_view()

constexpr Cogs::StringView::operator std::string_view ( ) const

inlineconstexprnoexcept

Implicit std::string_view conversion operator.

Provided to make StringView and std::string_view buddies (transition to std::string_view).

Returns

A std::string_view of the string view.

operator==()

bool Cogs::StringView::operator== ( const StringView &  other ) const

inline

Operator equal.

Compares this instance to the given StringView. To consider the string views equal, the length and content of the referenced strings must match exactly.

Parameters

other

StringView instance to compare this instance to.

Returns

A boolean indicating if the strings are equal.

References str, and strSize.

operator[]()

constexpr char Cogs::StringView::operator[] ( const size_t  index ) const

inlineconstexprnoexcept

Get the character at position index in the string.

Returns

Character at position index.

size()

constexpr size_t Cogs::StringView::size ( ) const

inlineconstexprnoexcept

Get the size of the string.

Equivalent to length().

Returns

Length of the string.

Referenced by Cogs::ImmutableString::ImmutableString(), and Cogs::Memory::MemoryBuffer::writeString().

split()

Cogs::StringView::Vector Cogs::StringView::split

(

const StringView &

delimiters

)

const

Split this string into parts.

References find_first_of(), and Cogs::Collections::SmallVectorImplBase< T, isPod >::push_back().

splitAll()

Cogs::StringView::Vector Cogs::StringView::splitAll

(

const StringView &

delimiters

)

const

Split this string into parts, empty parts will be retained.

References find_first_of(), and Cogs::Collections::SmallVectorImplBase< T, isPod >::push_back().

substr()

constexpr StringView Cogs::StringView::substr ( size_t  offset, size_t  count = NoPosition  ) const

inlineconstexprnoexcept

Get the given sub string.

to_string()

std::string Cogs::StringView::to_string

(

)

const

String conversion method.

Provided to match standard library API. Deprecated: Use std::string(StringViewObject) for portability when converting to std::string_view

Returns

A std::string object with a copy of the string held by this StringView.

References str, and strSize.

to_string_view()

constexpr std::string_view Cogs::StringView::to_string_view ( ) const

inlineconstexprnoexcept

Create a standard library string_view of the same view.

Deprecated: Use std::string_view(StringViewObject)

Returns

A std::string_view of the string view.

trim()

Cogs::StringView & Cogs::StringView::trim ( )

noexcept

Remove any whitespace from the start and end of this StringView's contents.

References trimEnd().

trimEnd()

Cogs::StringView & Cogs::StringView::trimEnd ( )

noexcept

Remove any whitespace from the end of this StringView's contents.

Referenced by trim().

trimStart()

Cogs::StringView & Cogs::StringView::trimStart ( )

noexcept

Remove any whitespace from the start of this StringView's contents.

Member Data Documentation

NoPosition

constexpr size_t Cogs::StringView::NoPosition = npos

staticconstexpr

No position.

npos

constexpr size_t Cogs::StringView::npos = static_cast<size_t>(-1)

staticconstexpr

No position.

str

const char* Cogs::StringView::str = nullptr

private

Pointer to the string this view is over.

Referenced by operator==(), and to_string().

strSize

size_t Cogs::StringView::strSize = 0

private

Length of the string data pointed to.

Referenced by operator==(), and to_string().

---

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

• Source/StringView.h
• Source/StringView.cpp