A string-like object that points to a sized piece of memory. More...

#include <stringpiece.h>

Inheritance diagram for icu::StringPiece:

Public Member Functions
	StringPiece ()
	Default constructor, creates an empty StringPiece.

	StringPiece (const char *str)
	Constructs from a NUL-terminated const char * pointer.

	StringPiece (const char8_t *str)
	Constructs from a NUL-terminated const char8_t * pointer.

	StringPiece (std::nullptr_t p)
	Constructs an empty StringPiece.

	StringPiece (const std::string &str)
	Constructs from a std::string.

	StringPiece (const std::u8string &str)
	Constructs from a std::u8string.

template<typename T , typename = std::enable_if_t< (std::is_same_v<decltype(T().data()), const char*> ) && std::is_same_v<decltype(T().size()), size_t>>>
	StringPiece (T str)
	Constructs from some other implementation of a string piece class, from any C++ record type that has these two methods:

	StringPiece (const char *offset, int32_t len)
	Constructs from a const char * pointer and a specified length.

	StringPiece (const char8_t *str, int32_t len)
	Constructs from a const char8_t * pointer and a specified length.

	StringPiece (const StringPiece &x, int32_t pos)
	Substring of another StringPiece.

	StringPiece (const StringPiece &x, int32_t pos, int32_t len)
	Substring of another StringPiece.

	operator std::string_view () const
	Converts to a std::string_view().

const char *	data () const
	Returns the string pointer.

int32_t	size () const
	Returns the string length.

int32_t	length () const
	Returns the string length.

UBool	empty () const
	Returns whether the string is empty.

void	clear ()
	Sets to an empty string.

void	set (const char *xdata, int32_t len)
	Reset the stringpiece to refer to new data.

void	set (const char *str)
	Reset the stringpiece to refer to new data.

void	set (const char8_t *xdata, int32_t len)
	Resets the stringpiece to refer to new data.

void	set (const char8_t *str)
	Resets the stringpiece to refer to new data.

void	remove_prefix (int32_t n)
	Removes the first n string units.

void	remove_suffix (int32_t n)
	Removes the last n string units.

int32_t	find (StringPiece needle, int32_t offset)
	Searches the StringPiece for the given search string (needle);.

int32_t	compare (StringPiece other)
	Compares this StringPiece with the other StringPiece, with semantics similar to std::string::compare().

StringPiece	substr (int32_t pos, int32_t len=npos) const
	Returns a substring of this StringPiece.

Static Public Attributes
static const int32_t	npos
	Maximum integer, used as a default value for substring methods.

Detailed Description

A string-like object that points to a sized piece of memory.

We provide non-explicit singleton constructors so users can pass in a "const char*" or a "string" wherever a "StringPiece" is expected.

Functions or methods may use StringPiece parameters to accept either a "const char*" or a "string" value that will be implicitly converted to a StringPiece.

Systematic usage of StringPiece is encouraged as it will reduce unnecessary conversions from "const char*" to "string" and back again.

Stable:: ICU 4.2

Definition at line 61 of file stringpiece.h.

Constructor & Destructor Documentation

◆ StringPiece() [1/11]

icu::StringPiece::StringPiece ( )

inline

Default constructor, creates an empty StringPiece.

Stable:: ICU 4.2

Definition at line 71 of file stringpiece.h.

◆ StringPiece() [2/11]

icu::StringPiece::StringPiece ( const char * str )

Constructs from a NUL-terminated const char * pointer.

Parameters

str	a NUL-terminated const char * pointer

Stable:: ICU 4.2

◆ StringPiece() [3/11]

icu::StringPiece::StringPiece ( const char8_t * str )

inline

Constructs from a NUL-terminated const char8_t * pointer.

Parameters

str	a NUL-terminated const char8_t * pointer

Stable:: ICU 67

Definition at line 85 of file stringpiece.h.

◆ StringPiece() [4/11]

icu::StringPiece::StringPiece ( std::nullptr_t p )

inline

Constructs an empty StringPiece.

Needed for type disambiguation from multiple other overloads.

Parameters

p nullptr

Stable:: ICU 67

Definition at line 93 of file stringpiece.h.

◆ StringPiece() [5/11]

icu::StringPiece::StringPiece ( const std::string & str )

inline

Constructs from a std::string.

Stable:: ICU 4.2

Definition at line 99 of file stringpiece.h.

◆ StringPiece() [6/11]

icu::StringPiece::StringPiece ( const std::u8string & str )

inline

Constructs from a std::u8string.

Stable:: ICU 67

Definition at line 106 of file stringpiece.h.

◆ StringPiece() [7/11]

template<typename T , typename = std::enable_if_t< (std::is_same_v<decltype(T().data()), const char*> ) && std::is_same_v<decltype(T().size()), size_t>>>

icu::StringPiece::StringPiece ( T str )

inline

Constructs from some other implementation of a string piece class, from any C++ record type that has these two methods:

struct OtherStringPieceClass {
  const char* data();  // or const char8_t*
  size_t size();
};

The other string piece class will typically be std::string_view from C++17 or absl::string_view from Abseil.

Starting with C++20, data() may also return a const char8_t* pointer, as from std::u8string_view.

Parameters

str	the other string piece

Stable:: ICU 65

Definition at line 141 of file stringpiece.h.

◆ StringPiece() [8/11]

icu::StringPiece::StringPiece	(	const char *	offset,
		int32_t	len
	)

inline

Constructs from a const char * pointer and a specified length.

Parameters

offset	a const char * pointer (need not be terminated)
len	the length of the string; must be non-negative

Stable:: ICU 4.2

Definition at line 151 of file stringpiece.h.

◆ StringPiece() [9/11]

icu::StringPiece::StringPiece	(	const char8_t *	str,
		int32_t	len
	)

inline

Constructs from a const char8_t * pointer and a specified length.

Parameters

str	a const char8_t * pointer (need not be terminated)
len	the length of the string; must be non-negative

Stable:: ICU 67

Definition at line 159 of file stringpiece.h.

◆ StringPiece() [10/11]

icu::StringPiece::StringPiece	(	const StringPiece &	x,
		int32_t	pos
	)

Substring of another StringPiece.

Parameters

x	the other StringPiece
pos	start position in x; must be non-negative and <= x.length().

Stable:: ICU 4.2

◆ StringPiece() [11/11]

icu::StringPiece::StringPiece	(	const StringPiece &	x,
		int32_t	pos,
		int32_t	len
	)

Substring of another StringPiece.

Parameters

x	the other StringPiece
pos	start position in x; must be non-negative and <= x.length().
len	length of the substring; must be non-negative and will be pinned to at most x.length() - pos.

Stable:: ICU 4.2

Member Function Documentation

◆ clear()

void icu::StringPiece::clear ( )

inline

Sets to an empty string.

Stable:: ICU 4.2

Definition at line 224 of file stringpiece.h.

◆ compare()

int32_t icu::StringPiece::compare ( StringPiece other )

Compares this StringPiece with the other StringPiece, with semantics similar to std::string::compare().

Parameters

other The string to compare to.

Returns: below zero if this < other; above zero if this > other; 0 if this == other.

Stable:: ICU 67

◆ data()

const char * icu::StringPiece::data ( ) const

inline

Returns the string pointer.

May be nullptr if it is empty.

data() may return a pointer to a buffer with embedded NULs, and the returned buffer may or may not be null terminated. Therefore it is typically a mistake to pass data() to a routine that expects a NUL terminated string.

Returns: the string pointer

Stable:: ICU 4.2

Definition at line 200 of file stringpiece.h.

◆ empty()

UBool icu::StringPiece::empty ( ) const

inline

Returns whether the string is empty.

Returns: true if the string is empty

Stable:: ICU 4.2

Definition at line 218 of file stringpiece.h.

◆ find()

int32_t icu::StringPiece::find	(	StringPiece	needle,
		int32_t	offset
	)

Searches the StringPiece for the given search string (needle);.

Parameters

needle	The string for which to search.
offset	Where to start searching within this string (haystack).

Returns: The offset of needle in haystack, or -1 if not found.

Stable:: ICU 67

◆ length()

int32_t icu::StringPiece::length ( ) const

inline

Returns the string length.

Same as size().

Returns: the string length

Stable:: ICU 4.2

Definition at line 212 of file stringpiece.h.

◆ operator std::string_view()

icu::StringPiece::operator std::string_view ( ) const

inline

Converts to a std::string_view().

Internal:: Do not use. This API is for internal use only.

Definition at line 185 of file stringpiece.h.

◆ remove_prefix()

void icu::StringPiece::remove_prefix ( int32_t n )

inline

Removes the first n string units.

Parameters

n	prefix length, must be non-negative and <=length()

Stable:: ICU 4.2

Definition at line 267 of file stringpiece.h.

◆ remove_suffix()

void icu::StringPiece::remove_suffix ( int32_t n )

inline

Removes the last n string units.

Parameters

n	suffix length, must be non-negative and <=length()

Stable:: ICU 4.2

Definition at line 282 of file stringpiece.h.

◆ set() [1/4]

void icu::StringPiece::set ( const char * str )

Reset the stringpiece to refer to new data.

Parameters

str	a pointer to a NUL-terminated string.

Stable:: ICU 4.8

◆ set() [2/4]

void icu::StringPiece::set	(	const char *	xdata,
		int32_t	len
	)

inline

Reset the stringpiece to refer to new data.

Parameters

xdata	pointer the new string data. Need not be nul terminated.
len	the length of the new data

Stable:: ICU 4.8

Definition at line 232 of file stringpiece.h.

◆ set() [3/4]

void icu::StringPiece::set ( const char8_t * str )

inline

Resets the stringpiece to refer to new data.

Parameters

str	a pointer to a NUL-terminated string.

Stable:: ICU 67

Definition at line 257 of file stringpiece.h.

◆ set() [4/4]

void icu::StringPiece::set	(	const char8_t *	xdata,
		int32_t	len
	)

inline

Resets the stringpiece to refer to new data.

Parameters

xdata	pointer the new string data. Need not be NUL-terminated.
len	the length of the new data

Stable:: ICU 67

Definition at line 248 of file stringpiece.h.

◆ size()

int32_t icu::StringPiece::size ( ) const

inline

Returns the string length.

Same as length().

Returns: the string length

Stable:: ICU 4.2

Definition at line 206 of file stringpiece.h.

◆ substr()

StringPiece icu::StringPiece::substr	(	int32_t	pos,
		int32_t	len = `npos`
	)		const

inline

Returns a substring of this StringPiece.

Parameters

pos	start position; must be non-negative and <= length().
len	length of the substring; must be non-negative and will be pinned to at most length() - pos.

Returns: the substring StringPiece

Stable:: ICU 4.2

Definition at line 324 of file stringpiece.h.

Field Documentation

◆ npos

const int32_t icu::StringPiece::npos

static

Maximum integer, used as a default value for substring methods.

Stable:: ICU 4.2

Definition at line 314 of file stringpiece.h.

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

common/unicode/stringpiece.h

Public Member Functions

Static Public Attributes

Detailed Description

Constructor & Destructor Documentation

◆ StringPiece() [1/11]

◆ StringPiece() [2/11]

◆ StringPiece() [3/11]

◆ StringPiece() [4/11]

◆ StringPiece() [5/11]

◆ StringPiece() [6/11]

◆ StringPiece() [7/11]

◆ StringPiece() [8/11]

◆ StringPiece() [9/11]

◆ StringPiece() [10/11]

◆ StringPiece() [11/11]

Member Function Documentation

◆ clear()

◆ compare()

◆ data()

◆ empty()

◆ find()

◆ length()

◆ operator std::string_view()

◆ remove_prefix()

◆ remove_suffix()

◆ set() [1/4]

◆ set() [2/4]

◆ set() [3/4]

◆ set() [4/4]

◆ size()

◆ substr()

Field Documentation

◆ npos