====== C++ Notes ======

===== Notes about the language =====

  * **C++11** is the ISO C++ standard ratified in 2011. The previous standard is often referred to as C++98 or C++03; the differences between C++98 and C++03 are so few and so technical that they ought not concern users. C++14 is the informal name for a recent revision of the C++ standard. It is intended to be a small extension over C++11, featuring mainly bug fixes and small improvements. 
  * **Differences between a class and a struct** in C++ are that structs have default public members and bases and classes have default private members and bases. Both classes and structs can have a mixture of public and private members, can use inheritance, and can have member functions. Classes create a namespace that also encapsulate the functions for manipulating its data elements. Classes may not be used when interfacing with C, because C does not have a concept of classes.

==== Maps ====

  * {{:wiki2:cpp:maps.pdf|Maps}}
===== Libraries =====
==== Use ====
Lets consider your ''/usr/local/lib/libYARP_OS.a''. What you can do is, have ''-L/usr/local/lib/'' in your makefile as one of the variables. And then you can have ''-lYARP_SO'' appended to the LDLIBS.

-L is for path to the lib and -l is the lib name here ''libYARP_OS''.a will be passed as ''-lYARP_OS''. On command line you would do something like: ''gcc -o main main.c -L/usr/local/lib/ -lYARP_SO''. This should give you an idea.

===== C++11 =====
==== Auto ====
<code cpp>
ofRectangle rectangle = ofGetCurrentViewport();
//is the same as
auto rectangle = ofGetCurrentViewport();

//and

const ofRectangle rectangle = ofGetCurrentViewport();
//is the same as
const auto rectangle = ofGetCurrentViewport();

float x = rectangle.x;
//is the same as
auto x = rectangle.x;

//and

float & x = rectangle.x;
//is the same as
auto & x = rectangle.x;
</code>



==== Foreach ====
<code cpp>
for (auto mySelfie : mySelfies) { ... }
// To use a reference rather than a copy
for(auto & mySelfie : mySelfies) { ... }
</code>

==== Override ====
This does not produces an error:
<code cpp>
class BuildingProjectionMapper {
public:
//...
    virtual void mapTheGreekColumns();
//...
};

class AutoBuildingProjectionMapper : public BuildingProjectionMapper {
public:
	void mapTheGreekColums(); // woops, I spelt column incorrectly
};
</code>
To solve this:
<code cpp>
class AutoBuildingProjectionMapper : public BuildingProjectionMapper {
public:
	void mapTheGreekColums() override;
};
</code>

===== Tips =====
  * Do not use ''this'' inside of a constructor.