C++: Difference between revisions

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=Usage=
How to do things using the [https://en.wikipedia.org/wiki/C%2B%2B_Standard_Library C++ standard library (stdlib)].
==Strings==
===String Interpolation===
[https://stackoverflow.com/questions/10410023/string-format-alternative-in-c Reference]
<syntaxhighlight lang="C++">
#include <iostream>
#include <sstream>
#include <string>


== Standard Library ==  
int main() {
 
    std::string a = "a", b = "b", c = "c";
=== Reading and Writing ===
    // apply formatting
    std::stringstream s;
    s << a << " " << b << " > " << c;
    // assign to std::string
    std::string str = s.str();
    std::cout << str << "\n";
}
</syntaxhighlight>
==Filesystem==
===Reading and Writing===
Reading and writing is done using <code>fstream</code>.<br>
Reading and writing is done using <code>fstream</code>.<br>
If you don't need r/w, use <code>istream</code> for reading or <code>ostream</code> for writing.<br>
If you don't need r/w, use <code>istream</code> for reading or <code>ostream</code> for writing.<br>
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</syntaxhighlight>
</syntaxhighlight>


===Regular Expressions===
==Regular Expressions==
[https://en.cppreference.com/w/cpp/regex Reference]
[https://en.cppreference.com/w/cpp/regex Reference]
<!--
<!--
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-->
-->


 
==Threading==
=== Sleep ===
=== Sleep ===
<syntaxhighlight lang="C++">
<syntaxhighlight lang="C++">
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</syntaxhighlight >
</syntaxhighlight >


==Memory==
=== Garbage Collection ===
=== Garbage Collection ===
Traditional C++ does not have garbage collection.   
Traditional C++ does not have garbage collection.   
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You can also use C allocation with `malloc`, `calloc`, `alloca`, and `free`.   
You can also use C allocation with `malloc`, `calloc`, `alloca`, and `free`.   
If using C++14, you can use [https://en.cppreference.com/w/cpp/memory/shared_ptr shared pointers] which does have automatic garbage collection.
If using C++14, you can use [https://en.cppreference.com/w/cpp/memory/shared_ptr shared pointers] which does have automatic garbage collection.
=Boost=
=STL=

Revision as of 12:38, 23 September 2019


Usage

How to do things using the C++ standard library (stdlib).

Strings

String Interpolation

Reference

#include <iostream>
#include <sstream>
#include <string>

int main() {
    std::string a = "a", b = "b", c = "c";
    // apply formatting
    std::stringstream s;
    s << a << " " << b << " > " << c;
    // assign to std::string
    std::string str = s.str();
    std::cout << str << "\n";
}

Filesystem

Reading and Writing

Reading and writing is done using fstream.
If you don't need r/w, use istream for reading or ostream for writing.

#include <iostream>
#include <fstream>

int main() {
  std::istream my_file("my_file.txt");
  std::string line;
  # Read line by line
  # You can also read using <<
  while (getline(my_file, line)) {
    std::cout << line << std::endl;
  }
  return 0;
}

Regular Expressions

Reference

Threading

Sleep

std::this_thread::sleep_for(std::chrono::milliseconds(1));

Memory

Garbage Collection

Traditional C++ does not have garbage collection.
After using `new` to allocate an object, use `delete` to deallocate it.
You can also use C allocation with `malloc`, `calloc`, `alloca`, and `free`.
If using C++14, you can use shared pointers which does have automatic garbage collection.

Boost

STL