zypp::C_Str Class Reference

Convenience char* constructible from std::string and char*, it maps (char*)0 to an empty string. More...

#include <String.h>

Public Types
typedef std::string::size_type	size_type

Public Member Functions
	C_Str ()
	C_Str (char *c_str_r)
	C_Str (const char *c_str_r)
	C_Str (const std::string &str_r)
bool	isNull () const
bool	empty () const
size_type	size () const
	operator const char * () const
const char *	c_str () const

Private Attributes
const char *const	_val
size_type	_sze

Related Functions
(Note that these are not member functions.)
std::ostream &	operator<< (std::ostream &str, const C_Str &obj)

Detailed Description

Convenience char* constructible from std::string and char*, it maps (char*)0 to an empty string.

bool hasPrefix( const std::string & str_r, const std::string & prefix_r )
{ return( ::strncmp( str_r.c_str(), prefix_r.c_str(), prefix_r.size() ) == 0 ); }

Called with a plain char* as argument, the std::string is created form for nothing. The implementation actually does not use the std::string.

Best would be to implement hasPrefix for each combination of char* and std::string arguments:

bool hasPrefix( const std::string & str_r, const std::string & prefix_r )
{ return( ::strncmp( str_r.c_str(), prefix_r.c_str(), prefix_r.size() ) == 0 ); }

bool hasPrefix( const std::string & str_r, const char * prefix_r )
{ return( !prefix_r || ::strncmp( str_r.c_str(), prefix_r, ::strlen(prefix_r) ) == 0 ); }

bool hasPrefix( const char * str_r, const std::string & prefix_r )
{ return( str_r ? ::strncmp( str_r, prefix_r.c_str(), prefix_r.size() ) == 0 : prefix_r.empty() ); }

bool hasPrefix( const char * str_r, const char * prefix_r )
{ return( str && prefix_r ? ::strncmp( str_r, prefix_r, ::strlen(prefix_r) ) == 0
                          : !((str_r && *str_r) || (prefix_r && *prefix_r)); }

This is where C_Str can help. Constructible from std::string and char*, it reduces the std::string to it's char*. At the same time it converts (char*)0 into an "" string.

bool hasPrefix( const C_Str & str_r, const C_Str & prefix_r )
{ return( ::strncmp( str_r, prefix_r, prefix_r.size() ) == 0 ); }

Definition at line 115 of file String.h.

Member Typedef Documentation

typedef std::string::size_type zypp::C_Str::size_type

Definition at line 118 of file String.h.

Constructor & Destructor Documentation

zypp::C_Str::C_Str ( )

inline

Definition at line 121 of file String.h.

zypp::C_Str::C_Str ( char *  c_str_r )

inline

Definition at line 122 of file String.h.

zypp::C_Str::C_Str ( const char *  c_str_r )

inline

Definition at line 123 of file String.h.

zypp::C_Str::C_Str ( const std::string &  str_r )

inline

Definition at line 124 of file String.h.

Member Function Documentation

bool zypp::C_Str::isNull ( ) const

inline

Definition at line 127 of file String.h.

bool zypp::C_Str::empty ( ) const

inline

Definition at line 128 of file String.h.

size_type zypp::C_Str::size ( ) const

inline

Definition at line 129 of file String.h.

zypp::C_Str::operator const char * ( ) const

inline

Definition at line 136 of file String.h.

const char* zypp::C_Str::c_str ( ) const

inline

Definition at line 137 of file String.h.

Friends And Related Function Documentation

std::ostream & operator<< ( std::ostream &  str, const C_Str &  obj  )

related

Stream output

Definition at line 145 of file String.h.

Member Data Documentation

const char* const zypp::C_Str::_val

private

Definition at line 140 of file String.h.

size_type zypp::C_Str::_sze

mutableprivate

Definition at line 141 of file String.h.

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

• zypp/base/String.h