ArmNN
 24.08
StringUtils.hpp
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1 //
2 // Copyright © 2020 Arm Ltd. All rights reserved.
3 // SPDX-License-Identifier: MIT
4 //
5 
6 #pragma once
7 
8 #include <iostream>
9 #include <sstream>
10 #include <algorithm>
11 #include <vector>
12 #include <armnn/Exceptions.hpp>
13 
14 namespace armnn
15 {
16 
17 namespace stringUtils
18 {
19 
20 /// Function to take a string and a list of delimiters and split the string into tokens based on those delimiters
21 /// This assumes that tokens are also to be split by newlines
22 /// Enabling tokenCompression merges adjacent delimiters together, preventing empty tokens
23 inline std::vector<std::string> StringTokenizer(const std::string& str,
24  const char* delimiters,
25  bool tokenCompression = true)
26 {
27  std::stringstream stringStream(str);
28  std::string line;
29  std::vector<std::string> tokenVector;
30  while (std::getline(stringStream, line))
31  {
32  std::size_t prev = 0;
33  std::size_t pos;
34  while ((pos = line.find_first_of(delimiters, prev)) != std::string::npos)
35  {
36  // Ignore adjacent tokens
37  if (pos > prev)
38  {
39  tokenVector.push_back(line.substr(prev, pos - prev));
40  }
41  // Unless token compression is disabled
42  else if (!tokenCompression)
43  {
44  tokenVector.push_back(line.substr(prev, pos - prev));
45  }
46  prev = pos + 1;
47  }
48  if (prev < line.length())
49  {
50  tokenVector.push_back(line.substr(prev, std::string::npos));
51  }
52  }
53  return tokenVector;
54 }
55 
56 // Set of 3 utility functions for trimming std::strings
57 // Default char set for common whitespace characters
58 
59 ///
60 /// Trim from the start of a string
61 ///
62 inline std::string& StringStartTrim(std::string& str, const std::string& chars = "\t\n\v\f\r ")
63 {
64  str.erase(0, str.find_first_not_of(chars));
65  return str;
66 }
67 
68 ///
69 /// Trim for the end of a string
70 ///
71 inline std::string& StringEndTrim(std::string& str, const std::string& chars = "\t\n\v\f\r ")
72 {
73  str.erase(str.find_last_not_of(chars) + 1);
74  return str;
75 }
76 
77 ///
78 /// Trim from both the start and the end of a string
79 ///
80 inline std::string& StringTrim(std::string& str, const std::string& chars = "\t\n\v\f\r ")
81 {
82  return StringStartTrim(StringEndTrim(str, chars), chars);
83 }
84 
85 ///
86 /// Trim from both the start and the end of a string, returns a trimmed copy of the string
87 ///
88 inline std::string StringTrimCopy(const std::string& str, const std::string& chars = "\t\n\v\f\r ")
89 {
90  std::string strCopy = str;
91  return StringStartTrim(StringEndTrim(strCopy, chars), chars);
92 }
93 
94 /// Takes a vector of strings and concatenates them together into one long std::string with an optional
95 /// seperator between each.
96 inline std::string StringConcat(const std::vector<std::string>& strings, std::string seperator = "")
97 {
98  std::stringstream ss;
99  for (auto string : strings)
100  {
101  ss << string << seperator;
102  }
103  return ss.str();
104 }
105 
106 ///
107 /// Iterates over a given str and replaces all instance of substring oldStr with newStr
108 ///
109 inline void StringReplaceAll(std::string& str,
110  const std::string& oldStr,
111  const std::string& newStr)
112 {
113  std::string::size_type pos = 0u;
114  while ((pos = str.find(oldStr, pos)) != std::string::npos)
115  {
116  str.replace(pos, oldStr.length(), newStr);
117  pos += newStr.length();
118  }
119 }
120 
121 ///
122 /// Converts a string to bool.
123 /// Accepts "true", "false" (case-insensitive) and numbers, 1 (true) or 0 (false).
124 ///
125 /// \param s String to convert to bool
126 /// \param throw_on_error Bool variable to suppress error if conversion failed (Will return false in that case)
127 /// \return bool value
128 ///
129 inline bool StringToBool(const std::string& s, bool throw_on_error = true)
130 {
131  // in case of failure to convert returns false
132  auto result = false;
133 
134  // isstringstream fails if parsing didn't work
135  std::istringstream is(s);
136 
137  // try integer conversion first. For the case s is a number
138  is >> result;
139 
140  if (is.fail())
141  {
142  // transform to lower case to make case-insensitive
143  std::string s_lower = s;
144  std::transform(s_lower.begin(),
145  s_lower.end(),
146  s_lower.begin(),
147  [](unsigned char c){ return std::tolower(c); });
148  is.str(s_lower);
149  // try boolean -> s="false" or "true"
150  is.clear();
151  is >> std::boolalpha >> result;
152  }
153 
154  if (is.fail() && throw_on_error)
155  {
156  throw armnn::InvalidArgumentException(s + " is not convertable to bool");
157  }
158 
159  return result;
160 }
161 
162 } // namespace stringUtils
163 
164 } // namespace armnn
armnn::stringUtils::StringStartTrim
std::string & StringStartTrim(std::string &str, const std::string &chars="\t\n\v\f\r ")
Trim from the start of a string.
Definition: StringUtils.hpp:62
armnn::stringUtils::StringConcat
std::string StringConcat(const std::vector< std::string > &strings, std::string seperator="")
Takes a vector of strings and concatenates them together into one long std::string with an optional s...
Definition: StringUtils.hpp:96
armnn::stringUtils::StringReplaceAll
void StringReplaceAll(std::string &str, const std::string &oldStr, const std::string &newStr)
Iterates over a given str and replaces all instance of substring oldStr with newStr.
Definition: StringUtils.hpp:109
armnn::stringUtils::StringToBool
bool StringToBool(const std::string &s, bool throw_on_error=true)
Converts a string to bool.
Definition: StringUtils.hpp:129
armnn::stringUtils::StringTrimCopy
std::string StringTrimCopy(const std::string &str, const std::string &chars="\t\n\v\f\r ")
Trim from both the start and the end of a string, returns a trimmed copy of the string.
Definition: StringUtils.hpp:88
armnn::stringUtils::StringTrim
std::string & StringTrim(std::string &str, const std::string &chars="\t\n\v\f\r ")
Trim from both the start and the end of a string.
Definition: StringUtils.hpp:80
armnn::InvalidArgumentException
Definition: Exceptions.hpp:80
armnn::stringUtils::StringEndTrim
std::string & StringEndTrim(std::string &str, const std::string &chars="\t\n\v\f\r ")
Trim for the end of a string.
Definition: StringUtils.hpp:71
Exceptions.hpp
armnn
Copyright (c) 2021 ARM Limited and Contributors.
Definition: 01_00_quick_start.dox:6
armnn::stringUtils::StringTokenizer
std::vector< std::string > StringTokenizer(const std::string &str, const char *delimiters, bool tokenCompression=true)
Function to take a string and a list of delimiters and split the string into tokens based on those de...
Definition: StringUtils.hpp:23