Does mql5 support deep copy?

[Yu Zhang]

Making pointers between classes, but I want to copy deeper, do MQL5 support?

[Alain Verleyen]

Why not ? It's up to you to decide.

[Alain Verleyen]

Memberwise copying of objects is performed in the implicit operator.

• If a member is an object, the corresponding copying operator for this object is called.
• If a member is an array of objects, the receiving array is increased or reduced to the require size using ArrayResize before calling the appropriate copying operator for each element.
  
• If a member is an array of simple types, the ArrayCopy function is used for copying.
• If a member is a pointer to an object, the pointer is copied rather than the object to which it points.

If necessary, you can override the behavior and create your own option instead of an implicit copy operator, using overloading.

See point 8 in the link.

[William Roeder]

Yu Zhang: Making pointers between classes, but I want to copy deeper, do MQL5 support?

If you want a deep copy, you write a copy constructor/assignment operator.

MQL5: Added automatic generation of an implicit copy operator for the objects of structures and classes. Now, the compiler automatically creates copy operators, which allows writing simple entries for objects, such as b=a:
          MetaTrader 5 Platform Beta Build 1625: Custom financial instruments - Stock Option Trading Strategies - General - MQL5 programming forum № 8 (2017)

Note that we did not have to overload the assignment operator "=", as structures of simple types can be directly copied one into each other. Thus, we can now write a code for calculations involving complex numbers in the usual manner.
          Language Basics / Functions / Operation Overloading - Reference on algorithmic/automated trading language for MetaTrader 5
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