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In VBA, an assignment of variables of type Object is a shallow copy, an assignment for all other types (numeric types, String, user defined types, arrays) is a deep copy. So the keyword Set for an assignment signals a shallow copy and the (optional) keyword Let signals a deep copy. There is no built-in method for deep copies of Objects in VBA.
If the default behavior ("shallow copy") is actually the intended one, then an explicit definition, although redundant, will be "self-documenting code" indicating that it was an intention rather than an oversight. Modern C++ includes a syntax for expressly specifying that a default function is desired without having to type out the function body.
In most programming languages (exceptions include Ruby), primitive types such as double, float, int, long, etc. simply store their values somewhere in the computer's memory (often the call stack). By using simple assignment, you can copy the contents of the variable to another one: Copying primitive types in Java or C++:
These cases are collectively called copy-initialization and are equivalent to: [2] T x = a; It is however, not guaranteed that a copy constructor will be called in these cases, because the C++ Standard allows the compiler to optimize the copy away in certain cases, one example being the return value optimization (sometimes referred to as RVO).
In C++ computer programming, copy elision refers to a compiler optimization technique that eliminates unnecessary copying of objects.. The C++ language standard generally allows implementations to perform any optimization, provided the resulting program's observable behavior is the same as if, i.e. pretending, the program were executed exactly as mandated by the standard.
In the C++ programming language, the assignment operator, =, is the operator used for assignment.Like most other operators in C++, it can be overloaded.. The copy assignment operator, often just called the "assignment operator", is a special case of assignment operator where the source (right-hand side) and destination (left-hand side) are of the same class type.
The effect of the as-if rule depends on the specific compiler implementation. As an example, in the Microsoft Visual C++ compiler, it causes omission of certain optimizations such as instruction reordering around calls to library functions, since such calls may cause input/output actions or accesses to memory locations marked volatile , and ...
A snippet of C code which prints "Hello, World!". The syntax of the C programming language is the set of rules governing writing of software in C. It is designed to allow for programs that are extremely terse, have a close relationship with the resulting object code, and yet provide relatively high-level data abstraction.