ICU 59.1  59.1
stringpiece.h
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1 // © 2016 and later: Unicode, Inc. and others.
2 // License & terms of use: http://www.unicode.org/copyright.html
3 // Copyright (C) 2009-2013, International Business Machines
4 // Corporation and others. All Rights Reserved.
5 //
6 // Copyright 2001 and onwards Google Inc.
7 // Author: Sanjay Ghemawat
8 
9 // This code is a contribution of Google code, and the style used here is
10 // a compromise between the original Google code and the ICU coding guidelines.
11 // For example, data types are ICU-ified (size_t,int->int32_t),
12 // and API comments doxygen-ified, but function names and behavior are
13 // as in the original, if possible.
14 // Assertion-style error handling, not available in ICU, was changed to
15 // parameter "pinning" similar to UnicodeString.
16 //
17 // In addition, this is only a partial port of the original Google code,
18 // limited to what was needed so far. The (nearly) complete original code
19 // is in the ICU svn repository at icuhtml/trunk/design/strings/contrib
20 // (see ICU ticket 6765, r25517).
21 
22 #ifndef __STRINGPIECE_H__
23 #define __STRINGPIECE_H__
24 
30 #include "unicode/utypes.h"
31 #include "unicode/uobject.h"
32 #include "unicode/std_string.h"
33 
34 // Arghh! I wish C++ literals were "string".
35 
37 
55  private:
56  const char* ptr_;
57  int32_t length_;
58 
59  public:
64  StringPiece() : ptr_(NULL), length_(0) { }
70  StringPiece(const char* str);
75  StringPiece(const std::string& str)
76  : ptr_(str.data()), length_(static_cast<int32_t>(str.size())) { }
83  StringPiece(const char* offset, int32_t len) : ptr_(offset), length_(len) { }
90  StringPiece(const StringPiece& x, int32_t pos);
99  StringPiece(const StringPiece& x, int32_t pos, int32_t len);
100 
111  const char* data() const { return ptr_; }
117  int32_t size() const { return length_; }
123  int32_t length() const { return length_; }
129  UBool empty() const { return length_ == 0; }
130 
135  void clear() { ptr_ = NULL; length_ = 0; }
136 
143  void set(const char* xdata, int32_t len) { ptr_ = xdata; length_ = len; }
144 
150  void set(const char* str);
151 
157  void remove_prefix(int32_t n) {
158  if (n >= 0) {
159  if (n > length_) {
160  n = length_;
161  }
162  ptr_ += n;
163  length_ -= n;
164  }
165  }
166 
172  void remove_suffix(int32_t n) {
173  if (n >= 0) {
174  if (n <= length_) {
175  length_ -= n;
176  } else {
177  length_ = 0;
178  }
179  }
180  }
181 
186  static const int32_t npos; // = 0x7fffffff;
187 
196  StringPiece substr(int32_t pos, int32_t len = npos) const {
197  return StringPiece(*this, pos, len);
198  }
199 };
200 
208 U_EXPORT UBool U_EXPORT2
209 operator==(const StringPiece& x, const StringPiece& y);
210 
218 inline UBool operator!=(const StringPiece& x, const StringPiece& y) {
219  return !(x == y);
220 }
221 
223 
224 #endif // __STRINGPIECE_H__
StringPiece(const char *offset, int32_t len)
Constructs from a const char * pointer and a specified length.
Definition: stringpiece.h:83
void remove_prefix(int32_t n)
Removes the first n string units.
Definition: stringpiece.h:157
int32_t size() const
Returns the string length.
Definition: stringpiece.h:117
U_EXPORT UBool operator==(const StringPiece &x, const StringPiece &y)
Global operator == for StringPiece.
UBool empty() const
Returns whether the string is empty.
Definition: stringpiece.h:129
#define U_NAMESPACE_BEGIN
This is used to begin a declaration of a public ICU C++ API.
Definition: uversion.h:131
StringPiece()
Default constructor, creates an empty StringPiece.
Definition: stringpiece.h:64
StringPiece(const std::string &str)
Constructs from a std::string.
Definition: stringpiece.h:75
UBool operator!=(const StringPiece &x, const StringPiece &y)
Global operator != for StringPiece.
Definition: stringpiece.h:218
#define NULL
Define NULL if necessary, to nullptr for C++ and to ((void *)0) for C.
Definition: utypes.h:188
C++ API: Central ICU header for including the C++ standard <string> header and for related definition...
int32_t length() const
Returns the string length.
Definition: stringpiece.h:123
C++ API: Common ICU base class UObject.
#define U_NAMESPACE_END
This is used to end a declaration of a public ICU C++ API.
Definition: uversion.h:132
StringPiece substr(int32_t pos, int32_t len=npos) const
Returns a substring of this StringPiece.
Definition: stringpiece.h:196
#define U_EXPORT
Definition: platform.h:830
const char * data() const
Returns the string pointer.
Definition: stringpiece.h:111
void clear()
Sets to an empty string.
Definition: stringpiece.h:135
Basic definitions for ICU, for both C and C++ APIs.
#define U_COMMON_API
Set to export library symbols from inside the common library, and to import them from outside...
Definition: utypes.h:359
A string-like object that points to a sized piece of memory.
Definition: stringpiece.h:54
void remove_suffix(int32_t n)
Removes the last n string units.
Definition: stringpiece.h:172
UMemory is the common ICU base class.
Definition: uobject.h:112
static const int32_t npos
Maximum integer, used as a default value for substring methods.
Definition: stringpiece.h:186
int8_t UBool
The ICU boolean type.
Definition: umachine.h:236