(C++) Trim

 

Trim is a std::string code snippet to remove leading and trailing whitespace from a std::string.

Technical facts

 

Operating system(s) or programming environment(s)

• Lubuntu 15.04 (vivid)

IDE(s):

• Qt Creator 3.1.1

Project type:

• Console application

C++ standard:

• C++98

Compiler(s):

• G++ 4.9.2

Libraries used:

• STL: GNU ISO C++ Library, version 4.9.2

 

 

 

 

 

Qt project file: ./CppTrim/CppTrim.pro

 

---

include(../../ConsoleApplication.pri) include(../../Libraries/Boost.pri) SOURCES += main.cpp

 

 

 

 

 

./CppTrim/main.cpp

 

---

#include <string> ///Trim leading and trailing whitespace //From http://www.richelbilderbeek.nl/CppTrim.htm std::string TrimStl(const std::string& s) {   const int size{static_cast<int>(s.size())};   int pos_begin = -1;   int pos_end = size-1;   for (int i=0; i!=size; ++i)   {     if (s[i]!=' ' && s[i]!='\n' && s[i]!='\t')     {       pos_begin = i; break;     }   }   if (pos_begin == -1) return "";   for (int i=size-1; i!=-1; --i)   {     if (s[i]!=' ' && s[i]!='\n' && s[i]!='\t')     {       pos_end = i; break;     }   }   return s.substr(pos_begin,pos_end-pos_begin+1); } #include <string> #include <boost/algorithm/string/trim.hpp> ///Trim leading and trailing whitespace //From http://www.richelbilderbeek.nl/CppTrim.htm const std::string TrimBoost(const std::string& s) {   return boost::algorithm::trim_copy(s); } int main() {   assert(TrimStl(" abc ") == "abc");   assert(TrimStl(" ab c ") != "abc");   assert(TrimBoost(" abc ") == "abc");   assert(TrimBoost(" ab c ") != "abc"); }