Examples of using Copy constructor in English and their translations into Ukrainian
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Colloquial
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Ecclesiastic
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Computer
Copy constructor.
Immediately answer this question:“Why do we need copy constructor?”.
The copy constructor in C++.
In it we will address all3 in which case it is desirable to use copy constructor.
The copy constructor in C++ PureCodeCpp.
The above code creates a temporary person object,and then assigns it to r using the copy constructor.
Copy constructor. Returns a copy of Range other.
These examples illustrate how copy constructors work and why they are required sometimes.
Copy constructor. Returns a copy of the cursor other.
The class will be created, containing no-argument constructor, copy constructor and destructor.
Copy constructor- during the making of copies of an object.
Contrary to expectations, a template copy constructor is not a user-defined copy constructor. .
Using copy constructor- a great way to get around these errors and problems.
However, if a class does not explicitly define a copy constructor, then C++ provides one by default.
In the 3rd block copy constructor is not invoked, respectively and 2nd no destructor.
At fourth block, during the declaration and initialization of a new object object2,load copy constructor.
The default copy constructor creates a bitwise(that is, identical) copy of the object.
Through declaration Object b= a;// translates as Object::Object(const Object&)(invoke copy constructor) b.
A copy constructor has as its first parameter a(possibly const or volatile) reference to its own class type.
Next, the function code is executed and during the return of the object in the main function main,load copy constructor.
Copy constructor required for, so that we can create“real”(not bitwise) copy the Object Class.
During transmission in it“object parameter” by value, load copy constructor and create“real” a copy of the object class OneClass.
The copy constructor and assignment operators of auto_ptr do not actually copy the stored pointer.
By the way, then, that the transfer of the object as a parameter by value, causes the copy constructor, serves as a good reason to pass an object by reference.
The compiler has generated a copy constructor for us, and it could be written like this: Person(const Person& other): age(other. age)// calls the copy constructor of the age{} So, when do we really need a user-defined copy constructor?
The following example demonstrates a scenario where the implementation may eliminate one orboth of the copies being made, even if the copy constructor has a visible side effect(printing text).
I highly recommend reading theme Copy constructor in the book by Stephen Prata“The programming language C++. Lectures and exercises. 6-edition.” It revealed a much deeper and includes all the basic nuances of using the copy constructor. .
An object can be assigned value using one of the two techniques: Explicit assignment in an expression Initialization Object a; Object b; a= b;// translates as Object:: operator=(const Object&), thus a. operator=(b) is called//(invoke simple copy, not copy constructor!).
The copy assignment operator differs from the copy constructor in that it must clean up the data members of the assignment's target(and correctly handle self-assignment) whereas the copy constructor assigns values to uninitialized data members.
For example: My_Array first;// initialization by default constructor My_Array second(first);// initialization by copy constructor My_Array third= first;// Also initialization by copy constructor second= third;// assignment by copy assignment operator The language permits an overloaded assignment operator to have an arbitrary return type(including void).