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Function templates (part 2)

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This lesson contains approximately 21 minutes of video content.

Template argument deduction

Templates and separate compilation

Additional Practice

Merlin's overloaded insertion operator

Drop your src and includes folders, the whole project folder, or individual files here, or click to choose files.

Merlin was showing off his operator overloading wizardry to his roomies. He asked them to “check out these lines of code”:

std::vector<int> vect; vect << 2; 
.-------------------.
| [0]       2       |
+-------------------+
|  0x7ffe3ac02ba0   |
'-------------------'
      Size : 1

And just like that, Merlin added the integer value 2 to the std::vector<int>. Shouts of glee could be heard from outside. He wasn’t through yet though, and showed off once more:

// executed after previous statements
vect << 7 << 11; 
.-------------------.
| [2]      11       |
+-------------------+
|  0x7ffe3ac02ba8   |
+-------------------+
| [1]       7       |
+-------------------+
|  0x7ffe3ac02ba4   |
+-------------------+
| [0]       2       |
+-------------------+
|  0x7ffe3ac02ba0   |
'-------------------'
      Size : 3

Having added two more values to vect using operator<<, the group’s excitement was heard across all of Aggieland. He then challenged his friends to define and declare an overloaded operator that does that exhibited here.

▶ TASKWrite the declaration and definition for an overloaded operator<< that adds an object of type T to the back of a std::vector<T>.

Make sure that your definition ensures that expressions such as vect << 2 and vect << 7 << 11 are evaluated correctly.

#include "utilities.hpp" #include <vector> int main() { }
#ifndef UTILITIES_HPP #define UTILITIES_HPP #endif
#include "utilities.hpp" // you should not use this file since you're defining a function template: the // function template's definition must be accessible in each translation unit so // that the compiler can derive a definition from the template to instantiate it // for some concrete type T.
> Click Run to compile and run your code.