glibmm: Glib::ustring Class Reference

Glib::ustring has much the same interface as std::string, but contains Unicode characters encoded as UTF-8. More...

#include <glibmm/ustring.h>

Inheritance diagram for Glib::ustring:

Public Types
using	size_type = std::string::size_type

using	difference_type = std::string::difference_type

using	value_type = gunichar

using	reference = gunichar&

using	const_reference = const gunichar&

using	iterator = ustring_Iterator< std::string::iterator >

using	const_iterator = ustring_Iterator< std::string::const_iterator >

using	reverse_iterator = std::reverse_iterator< iterator >

using	const_reverse_iterator = std::reverse_iterator< const_iterator >

Public Member Functions
	ustring ()

	~ustring () noexcept

	ustring (const ustring& other)

	ustring (ustring&& other)

ustring&	operator= (const ustring& other)

ustring&	operator= (ustring&& other)

void	swap (ustring& other)

	ustring (const std::string& src)

	ustring (std::string&& src)

	ustring (const ustring& src, size_type i, size_type n=npos)

	ustring (const char* src, size_type n)

	ustring (const char* src)

	ustring (size_type n, gunichar uc)

	ustring (size_type n, char c)

template<class In >
	ustring (In pbegin, In pend)

Assign new contents.
ustring&	operator= (const std::string& src)

ustring&	operator= (std::string&& src)

ustring&	operator= (const char* src)

ustring&	operator= (gunichar uc)

ustring&	operator= (char c)

ustring&	assign (const ustring& src)

ustring&	assign (ustring&& src)

ustring&	assign (const ustring& src, size_type i, size_type n)

ustring&	assign (const char* src, size_type n)

ustring&	assign (const char* src)

ustring&	assign (size_type n, gunichar uc)

ustring&	assign (size_type n, char c)

template<class In >
ustring&	assign (In pbegin, In pend)

Append to the string.
ustring&	operator+= (const ustring& src)

ustring&	operator+= (const char* src)

ustring&	operator+= (gunichar uc)

ustring&	operator+= (char c)

void	push_back (gunichar uc)

void	push_back (char c)

ustring&	append (const ustring& src)

ustring&	append (const ustring& src, size_type i, size_type n)

ustring&	append (const char* src, size_type n)

ustring&	append (const char* src)

ustring&	append (size_type n, gunichar uc)

ustring&	append (size_type n, char c)

template<class In >
ustring&	append (In pbegin, In pend)

Insert into the string.
ustring&	insert (size_type i, const ustring& src)

ustring&	insert (size_type i, const ustring& src, size_type i2, size_type n)

ustring&	insert (size_type i, const char* src, size_type n)

ustring&	insert (size_type i, const char* src)

ustring&	insert (size_type i, size_type n, gunichar uc)

ustring&	insert (size_type i, size_type n, char c)

iterator	insert (iterator p, gunichar uc)

iterator	insert (iterator p, char c)

void	insert (iterator p, size_type n, gunichar uc)

void	insert (iterator p, size_type n, char c)

template<class In >
void	insert (iterator p, In pbegin, In pend)

Replace sub-strings.
ustring&	replace (size_type i, size_type n, const ustring& src)

ustring&	replace (size_type i, size_type n, const ustring& src, size_type i2, size_type n2)

ustring&	replace (size_type i, size_type n, const char* src, size_type n2)

ustring&	replace (size_type i, size_type n, const char* src)

ustring&	replace (size_type i, size_type n, size_type n2, gunichar uc)

ustring&	replace (size_type i, size_type n, size_type n2, char c)

ustring&	replace (iterator pbegin, iterator pend, const ustring& src)

ustring&	replace (iterator pbegin, iterator pend, const char* src, size_type n)

ustring&	replace (iterator pbegin, iterator pend, const char* src)

ustring&	replace (iterator pbegin, iterator pend, size_type n, gunichar uc)

ustring&	replace (iterator pbegin, iterator pend, size_type n, char c)

template<class In >
ustring&	replace (iterator pbegin, iterator pend, In pbegin2, In pend2)

Erase sub-strings.
void	clear ()

ustring&	erase (size_type i, size_type n=npos)

ustring&	erase ()

iterator	erase (iterator p)

iterator	erase (iterator pbegin, iterator pend)

Compare and collate.
int	compare (UStringView rhs) const

int	compare (size_type i, size_type n, UStringView rhs) const

int	compare (size_type i, size_type n, const ustring& rhs, size_type i2, size_type n2) const

int	compare (size_type i, size_type n, const char* rhs, size_type n2) const

std::string	collate_key () const

std::string	casefold_collate_key () const

Extract characters and sub-strings.
value_type	operator[] (size_type i) const

value_type	at (size_type i) const

ustring	substr (size_type i=0, size_type n=npos) const

Access a sequence of characters.
iterator	begin ()

iterator	end ()

const_iterator	begin () const

const_iterator	end () const

reverse_iterator	rbegin ()

reverse_iterator	rend ()

const_reverse_iterator	rbegin () const

const_reverse_iterator	rend () const

const_iterator	cbegin () const

const_iterator	cend () const

Find sub-strings.
size_type	find (const ustring& str, size_type i=0) const

size_type	find (const char* str, size_type i, size_type n) const

size_type	find (const char* str, size_type i=0) const

size_type	find (gunichar uc, size_type i=0) const

size_type	find (char c, size_type i=0) const

size_type	rfind (const ustring& str, size_type i=npos) const

size_type	rfind (const char* str, size_type i, size_type n) const

size_type	rfind (const char* str, size_type i=npos) const

size_type	rfind (gunichar uc, size_type i=npos) const

size_type	rfind (char c, size_type i=npos) const

Match against a set of characters.
size_type	find_first_of (const ustring& match, size_type i=0) const

size_type	find_first_of (const char* match, size_type i, size_type n) const

size_type	find_first_of (const char* match, size_type i=0) const

size_type	find_first_of (gunichar uc, size_type i=0) const

size_type	find_first_of (char c, size_type i=0) const

size_type	find_last_of (const ustring& match, size_type i=npos) const

size_type	find_last_of (const char* match, size_type i, size_type n) const

size_type	find_last_of (const char* match, size_type i=npos) const

size_type	find_last_of (gunichar uc, size_type i=npos) const

size_type	find_last_of (char c, size_type i=npos) const

size_type	find_first_not_of (const ustring& match, size_type i=0) const

size_type	find_first_not_of (const char* match, size_type i, size_type n) const

size_type	find_first_not_of (const char* match, size_type i=0) const

size_type	find_first_not_of (gunichar uc, size_type i=0) const

size_type	find_first_not_of (char c, size_type i=0) const

size_type	find_last_not_of (const ustring& match, size_type i=npos) const

size_type	find_last_not_of (const char* match, size_type i, size_type n) const

size_type	find_last_not_of (const char* match, size_type i=npos) const

size_type	find_last_not_of (gunichar uc, size_type i=npos) const

size_type	find_last_not_of (char c, size_type i=npos) const

Retrieve the string's size.
bool	empty () const
	Returns true if the string is empty. More...

size_type	size () const
	Returns the number of characters in the string, not including any null-termination. More...

size_type	length () const
	This is the same as size(). More...

size_type	bytes () const
	Returns the number of bytes in the string, not including any null-termination. More...

Change the string's size.
void	resize (size_type n, gunichar uc)

void	resize (size_type n, char c= '\0')

Control the allocated memory.
size_type	capacity () const

size_type	max_size () const

void	reserve (size_type n=0)

Get a per-byte representation of the string.
	operator std::string () const

const std::string&	raw () const

const char*	data () const

const char*	c_str () const

size_type	copy (char* dest, size_type n, size_type i=0) const

UTF-8 utilities.
bool	validate () const

bool	validate (iterator& first_invalid)

bool	validate (const_iterator& first_invalid) const

ustring	make_valid () const

bool	is_ascii () const

ustring	normalize (NormalizeMode mode=NormalizeMode::DEFAULT_COMPOSE) const

Character case conversion.
ustring	uppercase () const

ustring	lowercase () const

ustring	casefold () const

Static Public Member Functions
Message formatting.
static ustring	compose (const ustring& fmt)

template<class... Ts>
static ustring	compose (const ustring& fmt, const Ts&...args)

template<class... Ts>
static ustring	format (const Ts&...args)

template<class... Ts>
static ustring	sprintf (const ustring& fmt, const Ts&...args)

template<class... Ts>
static ustring	sprintf (const char* fmt, const Ts&...args)

static ustring	sprintf (const ustring& fmt)

static ustring	sprintf (const char* fmt)

Static Public Attributes
static const size_type	npos = std::string::npos

Related Functions
(Note that these are not member functions.)
std::istream&	operator>> (std::istream& is, Glib::ustring& utf8_string)
	Stream input operator. More...

std::ostream&	operator<< (std::ostream& os, const Glib::ustring& utf8_string)
	Stream output operator. More...

std::wistream&	operator>> (std::wistream& is, ustring& utf8_string)
	Wide stream input operator. More...

std::wostream&	operator<< (std::wostream& os, const ustring& utf8_string)
	Wide stream output operator. More...

void	swap (ustring& lhs, ustring& rhs)

template<typename T , typename = std::enable_if_t<!std::is_base_of_v<ustring, T>>>
bool	operator== (const ustring& lhs, const T& rhs)

bool	operator== (UStringView lhs, const ustring& rhs)

template<typename T , typename = std::enable_if_t<!std::is_base_of_v<ustring, T>>>
bool	operator!= (const ustring& lhs, const T& rhs)

bool	operator!= (UStringView lhs, const ustring& rhs)

template<typename T , typename = std::enable_if_t<!std::is_base_of_v<ustring, T>>>
bool	operator< (const ustring& lhs, const T& rhs)

bool	operator< (UStringView lhs, const ustring& rhs)

template<typename T , typename = std::enable_if_t<!std::is_base_of_v<ustring, T>>>
bool	operator> (const ustring& lhs, const T& rhs)

bool	operator> (UStringView lhs, const ustring& rhs)

template<typename T , typename = std::enable_if_t<!std::is_base_of_v<ustring, T>>>
bool	operator<= (const ustring& lhs, const T& rhs)

bool	operator<= (UStringView lhs, const ustring& rhs)

template<typename T , typename = std::enable_if_t<!std::is_base_of_v<ustring, T>>>
bool	operator>= (const ustring& lhs, const T& rhs)

bool	operator>= (UStringView lhs, const ustring& rhs)

ustring	operator+ (const ustring& lhs, const ustring& rhs)

ustring	operator+ (const ustring& lhs, const char* rhs)

ustring	operator+ (const char* lhs, const ustring& rhs)

ustring	operator+ (const ustring& lhs, gunichar rhs)

ustring	operator+ (gunichar lhs, const ustring& rhs)

ustring	operator+ (const ustring& lhs, char rhs)

ustring	operator+ (char lhs, const ustring& rhs)

Detailed Description

Glib::ustring has much the same interface as std::string, but contains Unicode characters encoded as UTF-8.

About UTF-8 and ASCII

: The standard character set ANSI_X3.4-1968 – more commonly known as ASCII – is a subset of UTF-8. So, if you want to, you can use Glib::ustring without even thinking about UTF-8.

: Whenever ASCII is mentioned in this manual, we mean the real ASCII (i.e. as defined in ANSI_X3.4-1968), which contains only 7-bit characters. Glib::ustring can not be used with ASCII-compatible extended 8-bit charsets like ISO-8859-1. It's a good idea to avoid string literals containing non-ASCII characters (e.g. German umlauts) in source code, or at least you should use UTF-8 literals.

: You can find a detailed UTF-8 and Unicode FAQ here: http://www.cl.cam.ac.uk/~mgk25/unicode.html

Glib::ustring vs. std::string

: Glib::ustring has implicit type conversions to and from std::string. These conversions do not convert to/from the current locale (see Glib::locale_from_utf8() and Glib::locale_to_utf8() if you need that). You can always use std::string instead of Glib::ustring – however, using std::string with multi-byte characters is quite hard. For instance, std::string::operator[] might return a byte in the middle of a character, and std::string::length() returns the number of bytes rather than characters. So don't do that without a good reason.

: You cannot always use Glib::ustring instead of std::string.
Glib::ustring u("a_string_with_underscores");
std::replace(u.begin(), u.end(), '_', ' '); // does not compile
You can't use a Glib::ustring::iterator for writing to a Glib::ustring. See the documentation of Glib::ustring_Iterator for differences between it and std::string::iterator.

: Many member functions and operators of Glib::ustring and Glib::ustring_Iterator assume that the string contains only valid UTF-8 data. If it does not, memory outside the bounds of the string can be accessed. If you're uncertain, use validate() and/or make_valid().

: In a perfect world the C++ Standard Library would contain a UTF-8 string class. Unfortunately, the C++98 standard doesn't mention UTF-8 at all. C++11 has UTF-8 literals but no UTF-8 string class. Note that std::wstring is not a UTF-8 string class because it contains only fixed-width characters (where width could be 32, 16, or even 8 bits).

Glib::ustring and stream input/output

: The stream I/O operators, that is operator<<() and operator>>(), perform implicit charset conversion to/from the current locale. If that's not what you intended (e.g. when writing to a configuration file that should always be UTF-8 encoded) use ustring::raw() to override this behaviour.

: If you're using std::ostringstream to build strings for display in the user interface, you must convert the result back to UTF-8 as shown below:
std::locale::global(std::locale("")); // Set the global locale to the user's preferred locale.
// Usually unnecessary here, because Glib::init()
// does it for you.
std::ostringstream output;
output << percentage << " % done";
label->set_text(Glib::locale_to_utf8(output.str()));

Formatted output and internationalization

: The methods ustring::compose() and ustring::format() provide a convenient and powerful alternative to string streams, as shown in the example below. Refer to the method documentation of compose() and format() for details.
using Glib::ustring;
ustring message = ustring::compose("%1 is lower than 0x%2.",
12, ustring::format(std::hex, 16));

Implementation notes

: Glib::ustring does not inherit from std::string, because std::string was intended to be a final class. For instance, it does not have a virtual destructor. Also, a HAS-A relationship is more appropriate because ustring can't just enhance the std::string interface. Rather, it has to reimplement the interface so that all operations are based on characters instead of bytes.

Member Typedef Documentation

using Glib::ustring::const_iterator = ustring_Iterator<std::string::const_iterator>

using Glib::ustring::const_reference = const gunichar&

using Glib::ustring::const_reverse_iterator = std::reverse_iterator<const_iterator>

using Glib::ustring::difference_type = std::string::difference_type

using Glib::ustring::iterator = ustring_Iterator<std::string::iterator>

using Glib::ustring::reference = gunichar&

using Glib::ustring::reverse_iterator = std::reverse_iterator<iterator>

using Glib::ustring::size_type = std::string::size_type

using Glib::ustring::value_type = gunichar

Constructor & Destructor Documentation

Glib::ustring::ustring ( )

Default constructor, which creates an empty string.

Glib::ustring::~ustring ( )

noexcept

Glib::ustring::ustring ( const ustring& other )

Construct a ustring as a copy of another ustring.

Parameters

other A source string.

Glib::ustring::ustring ( ustring&& other )

Construct a ustring by moving from another ustring.

Parameters

other A source string.

Glib::ustring::ustring ( const std::string & src )

Construct a ustring as a copy of a std::string.

Parameters

src	A source `std::string` containing text encoded as UTF-8.

Glib::ustring::ustring ( std::string && src )

Construct a ustring by moving from a std::string.

Parameters

src	A source `std::string` containing text encoded as UTF-8.

Glib::ustring::ustring	(	const ustring&	src,
		size_type	i,
		size_type	n = `npos`
	)

Construct a ustring as a copy of a substring.

Parameters

src	Source ustring.
i	Index of first character to copy from.
n	Number of UTF-8 characters to copy (defaults to copying the remainder).

Glib::ustring::ustring	(	const char *	src,
		size_type	n
	)

Construct a ustring as a partial copy of a C string.

Parameters

src	Source C string encoded as UTF-8.
n	Number of UTF-8 characters to copy.

Glib::ustring::ustring ( const char * src )

Construct a ustring as a copy of a C string.

Parameters

src	Source C string encoded as UTF-8.

Glib::ustring::ustring	(	size_type	n,
		gunichar	uc
	)

Construct a ustring as multiple characters.

Parameters

n	Number of characters.
uc	UCS-4 code point to use.

Glib::ustring::ustring	(	size_type	n,
		char	c
	)

Construct a ustring as multiple characters.

Parameters

n	Number of characters.
c	ASCII character to use.

template <class In >

Glib::ustring::ustring	(	In	pbegin,
		In	pend
	)

Construct a ustring as a copy of a range.

Parameters

pbegin	Start of range.
pend	End of range.

Member Function Documentation

ustring& Glib::ustring::append ( const ustring& src )

ustring& Glib::ustring::append	(	const ustring&	src,
		size_type	i,
		size_type	n
	)

ustring& Glib::ustring::append	(	const char *	src,
		size_type	n
	)

ustring& Glib::ustring::append ( const char * src )

ustring& Glib::ustring::append	(	size_type	n,
		gunichar	uc
	)

ustring& Glib::ustring::append	(	size_type	n,
		char	c
	)

template <class In >

ustring& Glib::ustring::append	(	In	pbegin,
		In	pend
	)

ustring& Glib::ustring::assign ( const ustring& src )

ustring& Glib::ustring::assign ( ustring&& src )

ustring& Glib::ustring::assign	(	const ustring&	src,
		size_type	i,
		size_type	n
	)

ustring& Glib::ustring::assign	(	const char *	src,
		size_type	n
	)

ustring& Glib::ustring::assign ( const char * src )

ustring& Glib::ustring::assign	(	size_type	n,
		gunichar	uc
	)

ustring& Glib::ustring::assign	(	size_type	n,
		char	c
	)

template <class In >

ustring& Glib::ustring::assign	(	In	pbegin,
		In	pend
	)

value_type Glib::ustring::at ( size_type i ) const

No reference return; use replace() to write characters.

Exceptions

std::out_of_range

iterator Glib::ustring::begin ( )

const_iterator Glib::ustring::begin ( ) const

size_type Glib::ustring::bytes ( ) const

Returns the number of bytes in the string, not including any null-termination.

Returns: The number of bytes.

See also: size(), empty()

const char* Glib::ustring::c_str ( ) const

size_type Glib::ustring::capacity ( ) const

ustring Glib::ustring::casefold ( ) const

Returns a caseless representation of the UTF-8 string. The resulting string doesn't correspond to any particular case, therefore the result is only useful to compare strings and should never be displayed to the user.

std::string Glib::ustring::casefold_collate_key ( ) const

Create a unique key for the UTF-8 string that can be used for caseless sorting. ustr.casefold_collate_key() results in the same string as ustr.casefold().collate_key(), but the former is likely more efficient.

const_iterator Glib::ustring::cbegin ( ) const

Since glibmm 2.52:

const_iterator Glib::ustring::cend ( ) const

Since glibmm 2.52:

void Glib::ustring::clear ( )

std::string Glib::ustring::collate_key ( ) const

Create a unique sorting key for the UTF-8 string. If you need to compare UTF-8 strings regularly, e.g. for sorted containers such as std::set<>, you should consider creating a collate key first and compare this key instead of the actual string.

The ustring::compare() methods as well as the relational operators == != < > <= >= are quite costly because they have to deal with Unicode and the collation rules defined by the current locale. Converting both operands to UCS-4 is just the first of several costly steps involved when comparing ustrings. So be careful.

int Glib::ustring::compare ( UStringView rhs ) const

int Glib::ustring::compare	(	size_type	i,
		size_type	n,
		UStringView	rhs
	)		const

int Glib::ustring::compare	(	size_type	i,
		size_type	n,
		const ustring&	rhs,
		size_type	i2,
		size_type	n2
	)		const

int Glib::ustring::compare	(	size_type	i,
		size_type	n,
		const char *	rhs,
		size_type	n2
	)		const

static ustring Glib::ustring::compose ( const ustring& fmt )

inlinestatic

template <class... Ts>

static ustring Glib::ustring::compose	(	const ustring&	fmt,
		const Ts &...	args
	)

inlinestatic

Substitute placeholders in a format string with the referenced arguments.

The template string uses a similar format to Qt’s QString class, in that %1, %2, and so on to %9 are used as placeholders to be substituted with the string representation of the args 1–9, while %% inserts a literal % in the output. Placeholders do not have to appear in the same order as their corresponding function arguments.

Example:: using Glib::ustring;
const int percentage = 50;
const ustring text = ustring::compose("%1%% done", percentage);

Parameters

fmt	The template string, in the format described above.
args	1 to 9 arguments to substitute for `%1` to `%9` respectively.

Returns: The substituted message string.

Exceptions

Glib::ConvertError

Since glibmm 2.58:

size_type Glib::ustring::copy	(	char *	dest,
		size_type	n,
		size_type	i = `0`
	)		const

Returns: Number of copied bytes, not characters.

const char* Glib::ustring::data ( ) const

bool Glib::ustring::empty ( ) const

Returns true if the string is empty.

Equivalent to *this == "".

Returns: Whether the string is empty.

iterator Glib::ustring::end ( )

const_iterator Glib::ustring::end ( ) const

ustring& Glib::ustring::erase	(	size_type	i,
		size_type	n = `npos`
	)

ustring& Glib::ustring::erase ( )

iterator Glib::ustring::erase ( iterator p )

iterator Glib::ustring::erase	(	iterator	pbegin,
		iterator	pend
	)

size_type Glib::ustring::find	(	const ustring&	str,
		size_type	i = `0`
	)		const

size_type Glib::ustring::find	(	const char *	str,
		size_type	i,
		size_type	n
	)		const

size_type Glib::ustring::find	(	const char *	str,
		size_type	i = `0`
	)		const

size_type Glib::ustring::find	(	gunichar	uc,
		size_type	i = `0`
	)		const

size_type Glib::ustring::find	(	char	c,
		size_type	i = `0`
	)		const

size_type Glib::ustring::find_first_not_of	(	const ustring&	match,
		size_type	i = `0`
	)		const

size_type Glib::ustring::find_first_not_of	(	const char *	match,
		size_type	i,
		size_type	n
	)		const

size_type Glib::ustring::find_first_not_of	(	const char *	match,
		size_type	i = `0`
	)		const

size_type Glib::ustring::find_first_not_of	(	gunichar	uc,
		size_type	i = `0`
	)		const

size_type Glib::ustring::find_first_not_of	(	char	c,
		size_type	i = `0`
	)		const

size_type Glib::ustring::find_first_of	(	const ustring&	match,
		size_type	i = `0`
	)		const

size_type Glib::ustring::find_first_of	(	const char *	match,
		size_type	i,
		size_type	n
	)		const

size_type Glib::ustring::find_first_of	(	const char *	match,
		size_type	i = `0`
	)		const

size_type Glib::ustring::find_first_of	(	gunichar	uc,
		size_type	i = `0`
	)		const

size_type Glib::ustring::find_first_of	(	char	c,
		size_type	i = `0`
	)		const

size_type Glib::ustring::find_last_not_of	(	const ustring&	match,
		size_type	i = `npos`
	)		const

size_type Glib::ustring::find_last_not_of	(	const char *	match,
		size_type	i,
		size_type	n
	)		const

size_type Glib::ustring::find_last_not_of	(	const char *	match,
		size_type	i = `npos`
	)		const

size_type Glib::ustring::find_last_not_of	(	gunichar	uc,
		size_type	i = `npos`
	)		const

size_type Glib::ustring::find_last_not_of	(	char	c,
		size_type	i = `npos`
	)		const

size_type Glib::ustring::find_last_of	(	const ustring&	match,
		size_type	i = `npos`
	)		const

size_type Glib::ustring::find_last_of	(	const char *	match,
		size_type	i,
		size_type	n
	)		const

size_type Glib::ustring::find_last_of	(	const char *	match,
		size_type	i = `npos`
	)		const

size_type Glib::ustring::find_last_of	(	gunichar	uc,
		size_type	i = `npos`
	)		const

size_type Glib::ustring::find_last_of	(	char	c,
		size_type	i = `npos`
	)		const

template <class... Ts>

static ustring Glib::ustring::format ( const Ts &... args )

inlinestatic

Format the argument(s) to a string representation.

Applies the arguments in order to an std::wostringstream and returns the resulting string. I/O manipulators may also be used as arguments. This greatly simplifies the common task of converting a number to a string, as demonstrated by the example below. The format() methods can also be used in conjunction with compose() to facilitate localization of user-visible messages.

using Glib::ustring;
double value = 22.0 / 7.0;
ustring text = ustring::format(std::fixed, std::setprecision(2), value);

Note: The use of a wide character stream in the implementation of format() is almost completely transparent. However, one of the instances where the use of wide streams becomes visible is when the std::setfill() stream manipulator is used. In order for std::setfill() to work the argument must be of type wchar_t. This can be achieved by using the L prefix with a character literal, as shown in the example.

using Glib::ustring;
// Insert leading zeroes to fill in at least six digits
ustring text = ustring::format(std::setfill(L'0'), std::setw(6), 123);

Parameters

args	One or more streamable values or I/O manipulators.

Returns: The string representation of the argument stream.

Exceptions

Glib::ConvertError

Since glibmm 2.58:

ustring& Glib::ustring::insert	(	size_type	i,
		const ustring&	src
	)

ustring& Glib::ustring::insert	(	size_type	i,
		const ustring&	src,
		size_type	i2,
		size_type	n
	)

ustring& Glib::ustring::insert	(	size_type	i,
		const char *	src,
		size_type	n
	)

ustring& Glib::ustring::insert	(	size_type	i,
		const char *	src
	)

ustring& Glib::ustring::insert	(	size_type	i,
		size_type	n,
		gunichar	uc
	)

ustring& Glib::ustring::insert	(	size_type	i,
		size_type	n,
		char	c
	)

iterator Glib::ustring::insert	(	iterator	p,
		gunichar	uc
	)

iterator Glib::ustring::insert	(	iterator	p,
		char	c
	)

void Glib::ustring::insert	(	iterator	p,
		size_type	n,
		gunichar	uc
	)

void Glib::ustring::insert	(	iterator	p,
		size_type	n,
		char	c
	)

template <class In >

void Glib::ustring::insert	(	iterator	p,
		In	pbegin,
		In	pend
	)

bool Glib::ustring::is_ascii ( ) const

Check whether the string is plain 7-bit ASCII.

: Unlike any other ustring method, is_ascii() is safe to use on invalid UTF-8 strings. If the string isn't valid UTF-8, it cannot be valid ASCII either, therefore is_ascii() will just return false then.

Returns: Whether the string contains only ASCII characters.

size_type Glib::ustring::length ( ) const

This is the same as size().

ustring Glib::ustring::lowercase ( ) const

Returns a new UTF-8 string with all characters characters converted to their lowercase equivalent, while honoring the current locale. The resulting string may change in the number of bytes as well as in the number of characters.

ustring Glib::ustring::make_valid ( ) const

Return a copy that is a valid UTF-8 string replacing invalid bytes in the original with Unicode replacement character (U+FFFD). If the string is valid, return a copy of it.

size_type Glib::ustring::max_size ( ) const

ustring Glib::ustring::normalize ( NormalizeMode mode = NormalizeMode::DEFAULT_COMPOSE ) const

"Normalize" the Unicode character representation of the string.

Glib::ustring::operator std::string ( ) const

inline

ustring& Glib::ustring::operator+= ( const ustring& src )

ustring& Glib::ustring::operator+= ( const char * src )

ustring& Glib::ustring::operator+= ( gunichar uc )

ustring& Glib::ustring::operator+= ( char c )

ustring& Glib::ustring::operator= ( const ustring& other )

Assign the value of another string by copying to this string.

Parameters

other A source string.

ustring& Glib::ustring::operator= ( ustring&& other )

Assign the value of another string by moving to this string.

Parameters

other A source string.

ustring& Glib::ustring::operator= ( const std::string & src )

ustring& Glib::ustring::operator= ( std::string && src )

ustring& Glib::ustring::operator= ( const char * src )

ustring& Glib::ustring::operator= ( gunichar uc )

ustring& Glib::ustring::operator= ( char c )

value_type Glib::ustring::operator[] ( size_type i ) const

No reference return; use replace() to write characters.

void Glib::ustring::push_back ( gunichar uc )

void Glib::ustring::push_back ( char c )

const std::string& Glib::ustring::raw ( ) const

inline

reverse_iterator Glib::ustring::rbegin ( )

const_reverse_iterator Glib::ustring::rbegin ( ) const

reverse_iterator Glib::ustring::rend ( )

const_reverse_iterator Glib::ustring::rend ( ) const

ustring& Glib::ustring::replace	(	size_type	i,
		size_type	n,
		const ustring&	src
	)

ustring& Glib::ustring::replace	(	size_type	i,
		size_type	n,
		const ustring&	src,
		size_type	i2,
		size_type	n2
	)

ustring& Glib::ustring::replace	(	size_type	i,
		size_type	n,
		const char *	src,
		size_type	n2
	)

ustring& Glib::ustring::replace	(	size_type	i,
		size_type	n,
		const char *	src
	)

ustring& Glib::ustring::replace	(	size_type	i,
		size_type	n,
		size_type	n2,
		gunichar	uc
	)

ustring& Glib::ustring::replace	(	size_type	i,
		size_type	n,
		size_type	n2,
		char	c
	)

ustring& Glib::ustring::replace	(	iterator	pbegin,
		iterator	pend,
		const ustring&	src
	)

ustring& Glib::ustring::replace	(	iterator	pbegin,
		iterator	pend,
		const char *	src,
		size_type	n
	)

ustring& Glib::ustring::replace	(	iterator	pbegin,
		iterator	pend,
		const char *	src
	)

ustring& Glib::ustring::replace	(	iterator	pbegin,
		iterator	pend,
		size_type	n,
		gunichar	uc
	)

ustring& Glib::ustring::replace	(	iterator	pbegin,
		iterator	pend,
		size_type	n,
		char	c
	)

template <class In >

ustring& Glib::ustring::replace	(	iterator	pbegin,
		iterator	pend,
		In	pbegin2,
		In	pend2
	)

void Glib::ustring::reserve ( size_type n = 0 )

void Glib::ustring::resize	(	size_type	n,
		gunichar	uc
	)

void Glib::ustring::resize	(	size_type	n,
		char	c = `'\0'`
	)

size_type Glib::ustring::rfind	(	const ustring&	str,
		size_type	i = `npos`
	)		const

size_type Glib::ustring::rfind	(	const char *	str,
		size_type	i,
		size_type	n
	)		const

size_type Glib::ustring::rfind	(	const char *	str,
		size_type	i = `npos`
	)		const

size_type Glib::ustring::rfind	(	gunichar	uc,
		size_type	i = `npos`
	)		const

size_type Glib::ustring::rfind	(	char	c,
		size_type	i = `npos`
	)		const

size_type Glib::ustring::size ( ) const

Returns the number of characters in the string, not including any null-termination.

Returns: The number of UTF-8 characters.

See also: bytes(), empty()

template <class... Ts>

static ustring Glib::ustring::sprintf	(	const ustring&	fmt,
		const Ts &...	args
	)

inlinestatic

Substitute placeholders in a format string with the referenced arguments.

This function takes a template string in the format used by C’s printf() family of functions and an arbitrary number of arguments, replaces each placeholder in the template with the formatted version of its corresponding argument at the same ordinal position in the list of subsequent arguments, and returns the result in a new Glib::ustring.

Note: You must pass the correct count/types/order of arguments to match the format string, as when calling printf() directly. glibmm does not check this for you. Breaking this contract invokes undefined behavior and is a security risk.

The exception is that glibmm special-cases std::string and Glib::ustring, so you can pass them in positions corresponding to s placeholders without having to call their .c_str() functions; glibmm does that for you. glibmm also overloads sprintf() with fmt but no args to avoid risks.

Said restriction also makes sprintf() unsuitable for translatable strings, as translators cannot reorder the placeholders to suit their language. If you wish to support translation, you should instead use compose(), as its placeholders are numbered rather than ordinal, so they can be moved freely.

Example:: const auto greeting = std::string{"Hi"};
const auto name = Glib::ustring{"Dennis"};
const auto your_cows = 3;
const auto my_cows = 11;
const auto cow_percentage = 100.0 * your_cows / my_cows;
const auto text = Glib::ustring::sprintf(
"%s, %s! You have %d cows. That's about %0.2f%% of the %d cows I have.",
greeting, name, your_cows, cow_percentage, my_cows);
std::cout << text;
// Hi, Dennis! You have 3 cows. That's about 27.27% of the 11 cows I have.

Parameters

fmt	The template string, in the format used by `printf()` et al.
args	A set of arguments having the count/types/order required by fmt.

Returns: The substituted string.

Since glibmm 2.62:

template <class... Ts>

static ustring Glib::ustring::sprintf	(	const char *	fmt,
		const Ts &...	args
	)

inlinestatic

Overload of sprintf() taking a string literal.

The main benefit of this is not constructing a temporary ustring if fmt is a string literal. A secondary effect is that it might encourage compilers to check if the given format fmt matches the variadic arguments args. The latter effect is a convenience at best; you must not rely on it to find errors in your code, as your compiler might not always be able to do so.

Parameters

fmt	The template string, in the format used by `printf()` et al.
args	A set of arguments having the count/types/order required by fmt.

Returns: The substituted string.

Since glibmm 2.62:

static ustring Glib::ustring::sprintf ( const ustring& fmt )

inlinestatic

Overload of sprintf() for a format string only, which returns it unchanged.

If no args to be substituted are given, there is nothing to do, so the fmt string is returned as-is without substitution. This is an obvious case of mismatched format/args that we can check. Not doing so causes warnings/errors with common compiler options, as it is a security risk.

Parameters

fmt	The string

Returns: The same string.

Since glibmm 2.62:

static ustring Glib::ustring::sprintf ( const char * fmt )

inlinestatic

Overload of sprintf() for a format string only, which returns it unchanged and avoids creating a temporary ustring as the argument.

Parameters

fmt	The string

Returns: The same string, as a ustring.

Since glibmm 2.62:

ustring Glib::ustring::substr	(	size_type	i = `0`,
		size_type	n = `npos`
	)		const

inline

void Glib::ustring::swap ( ustring& other )

Swap contents with another string.

Parameters

other String to swap with.

ustring Glib::ustring::uppercase ( ) const

Returns a new UTF-8 string with all characters characters converted to their uppercase equivalent, while honoring the current locale. The resulting string may change in the number of bytes as well as in the number of characters. For instance, the German sharp s "ß" will be replaced by two characters "SS" because there is no capital "ß".

bool Glib::ustring::validate ( ) const

Check whether the string is valid UTF-8.

bool Glib::ustring::validate ( iterator& first_invalid )

Check whether the string is valid UTF-8.

bool Glib::ustring::validate ( const_iterator& first_invalid ) const

Check whether the string is valid UTF-8.

Friends And Related Function Documentation

template <typename T , typename = std::enable_if_t<!std::is_base_of_v<ustring, T>>>

bool operator!=	(	const ustring&	lhs,
		const T &	rhs
	)

bool operator!=	(	UStringView	lhs,
		const ustring&	rhs
	)

ustring operator+	(	const ustring&	lhs,
		const ustring&	rhs
	)

ustring operator+	(	const ustring&	lhs,
		const char *	rhs
	)

ustring operator+	(	const char *	lhs,
		const ustring&	rhs
	)

ustring operator+	(	const ustring&	lhs,
		gunichar	rhs
	)

ustring operator+	(	gunichar	lhs,
		const ustring&	rhs
	)

ustring operator+	(	const ustring&	lhs,
		char	rhs
	)

ustring operator+	(	char	lhs,
		const ustring&	rhs
	)

template <typename T , typename = std::enable_if_t<!std::is_base_of_v<ustring, T>>>

bool operator<	(	const ustring&	lhs,
		const T &	rhs
	)

bool operator<	(	UStringView	lhs,
		const ustring&	rhs
	)

std::ostream & operator<<	(	std::ostream &	os,
		const Glib::ustring&	utf8_string
	)

Stream output operator.

Exceptions

Glib::ConvertError

std::wostream & operator<<	(	std::wostream &	os,
		const ustring&	utf8_string
	)

Wide stream output operator.

Exceptions

Glib::ConvertError

template <typename T , typename = std::enable_if_t<!std::is_base_of_v<ustring, T>>>

bool operator<=	(	const ustring&	lhs,
		const T &	rhs
	)

bool operator<=	(	UStringView	lhs,
		const ustring&	rhs
	)

template <typename T , typename = std::enable_if_t<!std::is_base_of_v<ustring, T>>>

bool operator==	(	const ustring&	lhs,
		const T &	rhs
	)

bool operator==	(	UStringView	lhs,
		const ustring&	rhs
	)

template <typename T , typename = std::enable_if_t<!std::is_base_of_v<ustring, T>>>

bool operator>	(	const ustring&	lhs,
		const T &	rhs
	)

bool operator>	(	UStringView	lhs,
		const ustring&	rhs
	)

template <typename T , typename = std::enable_if_t<!std::is_base_of_v<ustring, T>>>

bool operator>=	(	const ustring&	lhs,
		const T &	rhs
	)

bool operator>=	(	UStringView	lhs,
		const ustring&	rhs
	)

std::istream & operator>>	(	std::istream &	is,
		Glib::ustring&	utf8_string
	)

Stream input operator.

Exceptions

Glib::ConvertError

std::wistream & operator>>	(	std::wistream &	is,
		ustring&	utf8_string
	)

Wide stream input operator.

Exceptions

Glib::ConvertError GLIBMM_API

void swap	(	ustring&	lhs,
		ustring&	rhs
	)

Member Data Documentation

const size_type Glib::ustring::npos = std::string::npos

static

glibmm: Glib::ustring Class Reference

Public Types

Public Member Functions

Static Public Member Functions

Static Public Attributes

Related Functions

Detailed Description

Member Typedef Documentation

Constructor & Destructor Documentation

Member Function Documentation

Friends And Related Function Documentation

Member Data Documentation