![]() Yet, if a is an object of class Array, most people think that a = 7 makes sense even though a is really just a function call in disguise (it calls Array::operator(int), which is the subscript operator for class Array). For example, no one thinks the expression f() = 7 makes sense. The function call can appear on the left hand side of an assignment operator. In compiler writer lingo, a reference is an “lvalue” (something that can appear on the left hand side of an assignment operator). Remember: the reference is the referent, so changing the reference changes the state of the referent. You change the state of the referent (the referent is the object to which the reference refers). What happens if you assign to a reference? There is no C++ syntax that lets you operate on the reference itself separate from the object to which it refers. It is neither a pointer to the object, nor a copy of the object. Out of the four altenatives suggested select the one which best expresses the. A reference is the object, just with another name. DIRECTIONS for the question 1 to 15: A sentence has been given in Direct Speech. Important note: Even though a reference is often implemented using an address in the underlying assembly language, please do not think of a reference as a funny looking pointer to an object. In other words, a C programmer will think of i as a macro for (*p), where p is a pointer to x (e.g., the compiler automatically dereferences the underlying pointer i++ is changed to (*p)++ i = 7 is automatically changed to *p = 7). If you used the C style pass-by-pointer, with the syntactic variant of (1) moving the & from the caller into the callee, and (2) eliminating the *s. In particular, the address bits that the compiler uses to find x are not changed. But when the programmer says i++, the compiler generates code that increments x. Leon time zone is Eastern Daylight Time which is 5 hours behind Coordinated Universal Time (UTC). Leon, browse local businesses, landmarks, get current traffic estimates, road conditions, and more. Underneath it all, a reference i to object x is typically the machine address of the object x. Leon is located in Dearborn County in the State of Indiana. Now, at the risk of confusing you by giving you a different perspective, here’s how references are implemented. That’s how you should think of references as a programmer. Anything you do to i gets done to x, and vice versa. In other words, i is x - not a pointer to x, nor a copy of x, but x itself. Here i and j are aliases for main’s x and y respectively. References are frequently used for pass-by-reference: void swap(int& i, int& j) An alias (an alternate name) for an object.
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