v1::grapheme Struct Reference

#include <hikogui/unicode/grapheme.hpp>

Public Types
using	value_type = uint32_t

Public Member Functions
constexpr	grapheme (grapheme const &) noexcept=default
constexpr	grapheme (grapheme &&) noexcept=default
constexpr grapheme &	operator= (grapheme const &) noexcept=default
constexpr grapheme &	operator= (grapheme &&) noexcept=default
constexpr	grapheme (nullptr_t) noexcept
constexpr	grapheme (char32_t code_point) noexcept
	Encode a single code-point.
constexpr	grapheme (char ascii_char) noexcept
constexpr grapheme &	operator= (char32_t code_point) noexcept
	Encode a single code-point.
constexpr grapheme &	operator= (char ascii_char) noexcept
	Encode a single code-point.
	grapheme (std::u32string_view code_points) noexcept
	Encode a grapheme from a list of code-points.
	grapheme (composed_t, std::u32string_view code_points) noexcept
	Encode a grapheme from a list of code-points.
constexpr void	clear () noexcept
	Clear the grapheme.
constexpr bool	empty () const noexcept
	Check if the grapheme is empty.
constexpr	operator bool () const noexcept
	Check if the grapheme holds any code-points.
bool	valid () const noexcept
	Check if the grapheme is valid.
std::u32string const &	long_grapheme () const noexcept
constexpr std::size_t	size () const noexcept
	Return the number of code-points encoded in the grapheme.
constexpr char32_t	operator[] (size_t i) const noexcept
	Get the code-point at the given index.
constexpr std::u32string	composed () const noexcept
	Get a list of code-point normalized to NFC.
std::u32string	decomposed () const noexcept
	Get a list of code-point normalized to NFD.

Static Public Member Functions
static constexpr grapheme	eof () noexcept
	Create empty grapheme / end-of-file.

Data Fields
value_type	_value
	A pointer to a grapheme.

Friends
template<size_t I>
constexpr char32_t	get (grapheme const &rhs) noexcept
	Get the code-point at the given index.
constexpr bool	operator== (grapheme const &, grapheme const &) noexcept=default
	Compare equivalence of two graphemes.
constexpr std::strong_ordering	operator<=> (grapheme const &lhs, grapheme const &rhs) noexcept
	Compare two graphemes lexicographically.
constexpr bool	operator== (grapheme const &lhs, char32_t const &rhs) noexcept
constexpr std::strong_ordering	operator<=> (grapheme const &lhs, char32_t const &rhs) noexcept
constexpr bool	operator== (grapheme const &lhs, char const &rhs) noexcept
constexpr std::strong_ordering	operator<=> (grapheme const &lhs, char const &rhs) noexcept
std::string	to_string (grapheme const &rhs) noexcept
std::u32string	to_u32string (grapheme const &rhs) noexcept

Detailed Description

A grapheme-cluster, what a user thinks a character is.

A grapheme should not include typographical ligatures such as 'fi' as the font should handle creating ligatures.

If a grapheme is initialized with more than 1 code-points a long_grapheme is allocated. This grapheme is never deleted from memory.

This class is trivial and constant-destructible so that it can be used as a character class in std::basic_string and used as a non-type template parameter.

Constructor & Destructor Documentation

grapheme() [1/3]

constexpr v1::grapheme::grapheme ( char32_t code_point )

inlineexplicitconstexprnoexcept

Encode a single code-point.

grapheme() [2/3]

v1::grapheme::grapheme ( std::u32string_view code_points )

explicitnoexcept

Encode a grapheme from a list of code-points.

Parameters

code_points

The non-normalized list of code-points.

grapheme() [3/3]

v1::grapheme::grapheme ( composed_t , std::u32string_view code_points )

explicitnoexcept

Encode a grapheme from a list of code-points.

Parameters

code_points

The NFC/NKFC normalized and composed code-point of this grapheme.

Member Function Documentation

clear()

constexpr void v1::grapheme::clear ( )

inlineconstexprnoexcept

Clear the grapheme.

composed()

constexpr std::u32string v1::grapheme::composed ( ) const

inlineconstexprnoexcept

Get a list of code-point normalized to NFC.

decomposed()

std::u32string v1::grapheme::decomposed ( ) const

noexcept

Get a list of code-point normalized to NFD.

empty()

constexpr bool v1::grapheme::empty ( ) const

inlineconstexprnoexcept

Check if the grapheme is empty.

eof()

static constexpr grapheme v1::grapheme::eof ( )

inlinestaticconstexprnoexcept

Create empty grapheme / end-of-file.

operator bool()

constexpr v1::grapheme::operator bool ( ) const

inlineconstexprnoexcept

Check if the grapheme holds any code-points.

operator=() [1/2]

constexpr grapheme & v1::grapheme::operator= ( char ascii_char )

inlineconstexprnoexcept

Encode a single code-point.

operator=() [2/2]

constexpr grapheme & v1::grapheme::operator= ( char32_t code_point )

inlineconstexprnoexcept

Encode a single code-point.

operator[]()

constexpr char32_t v1::grapheme::operator[] ( size_t i ) const

inlineconstexprnoexcept

Get the code-point at the given index.

Note

It is undefined-behavior to index beyond the number of encoded code-points.

Parameters

i	Index of code-point in the grapheme.

Returns

code-point at the given index.

size()

constexpr std::size_t v1::grapheme::size ( ) const

inlineconstexprnoexcept

Return the number of code-points encoded in the grapheme.

valid()

bool v1::grapheme::valid ( ) const

noexcept

Check if the grapheme is valid.

A grapheme is invalid in case:

• The grapheme is empty.
• The first code-point is part of general category 'C'.
• The first code-point is a combining character; canonical combining class != 0.

Friends And Related Symbol Documentation

get

template<size_t I>

constexpr char32_t get ( grapheme const & rhs )

friend

Get the code-point at the given index.

Note

It is undefined-behavior to index beyond the number of encoded code-points.

Template Parameters

I	Index of code-point in the grapheme.

Parameters

rhs	The grapheme to query.

Returns

code-point at the given index.

operator<=>

constexpr std::strong_ordering operator<=> ( grapheme const & lhs, grapheme const & rhs )

friend

Compare two graphemes lexicographically.

operator==

constexpr bool operator== ( grapheme const & , grapheme const &  )

friend

Compare equivalence of two graphemes.

Field Documentation

_value

value_type v1::grapheme::_value

A pointer to a grapheme.

This class will hold:

• A single code point between U+0000 to U+10ffff, or
• An index + 0x110000 into the long_graphemes table, or
• 0x1fffff meaning empty/eof.

Bits [31:21] are always '0'.

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

• hikogui/src/hikogui/unicode/grapheme.hpp