mongo::StringData Class Reference

A StringData object wraps a 'const string&' or a 'const char*' without copying its contents. More...

#include <string_data.h>

Classes
struct	Hasher
	Functor compatible with std::hash for std::unordered_{map,set} Warning: The hash function is subject to change. More...
struct	LiteralTag
	Constructs a StringData explicitly, for the case of a literal whose size is known at compile time. More...

Public Member Functions
	StringData ()
	Constructs an empty string data.
	StringData (const char *str)
	Constructs a StringData, for the case where the length of string is not known. More...
	StringData (const char *c, size_t len)
	Constructs a StringData explicitly, for the case where the length of the string is already known. More...
	StringData (const std::string &s)
	Constructs a StringData, for the case of a string. More...
int	compare (const StringData &other) const
	Returns -1, 0, or 1 if 'this' is less, equal, or greater than 'other' in lexicographical order.
bool	equalCaseInsensitive (const StringData &other) const
	note: this uses tolower, and therefore does not handle come languages correctly. More...
bool	startsWith (const StringData &prefix) const
	Returns true if 'prefix' is a substring of this instance, anchored at position 0.
bool	endsWith (const StringData &suffix) const
	Returns true if 'suffix' is a substring of this instance, anchored at the end.
const char *	rawData () const
	Get the pointer to the first byte of StringData. More...

Detailed Description

A StringData object wraps a 'const string&' or a 'const char*' without copying its contents.

The most common usage is as a function argument that takes any of the two forms of strings above. Fundamentally, this class tries go around the fact that string literals in C++ are char[N]'s.

Notes:

• The object StringData wraps around must be alive while the StringData is.
• Because string data can be used to pass a substring around, one should never assume a rawData() terminates with a null.

Constructor & Destructor Documentation

mongo::StringData::StringData ( const char *  str )

inline

Constructs a StringData, for the case where the length of string is not known.

'c' must be a pointer to a null-terminated string.

mongo::StringData::StringData ( const char *  c, size_t  len  )

inline

Constructs a StringData explicitly, for the case where the length of the string is already known.

'c' must be a pointer to a null-terminated string, and len must be the length that strlen(c) would return, a.k.a the index of the terminator in c.

mongo::StringData::StringData ( const std::string &  s )

inline

Constructs a StringData, for the case of a string.

Member Function Documentation

bool mongo::StringData::equalCaseInsensitive ( const StringData &  other ) const

inline

note: this uses tolower, and therefore does not handle come languages correctly.

should be use sparingly

const char* mongo::StringData::rawData ( ) const

inline

Get the pointer to the first byte of StringData.

This is not guaranteed to be null-terminated, so if using this without checking size(), you are likely doing something wrong.

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

• src/mongo/base/string_data.h
• src/mongo/base/string_data-inl.h