function - C++ returns objects by value -

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the topic pretty in title of question. saw in meyrses book "effective c++":

the fact c++ returns objects value

what mean , how c++ standard supports message? instanance, have this:

int foo() {     int = 1;     return a; }

that's pretty clear, phrase mean returns copy of value stored in local variable. consider this:

int& foo() {     int = 1;     return a; }

a compiler should warn returning reference local variable. how "returning value fact" apply example?

meyers correct in main, though have take wording pinch of salt when dealing references. @ level of abstraction, here you're passing reference "by value".

but he's trying that, beyond that, c++ passes value default, , contrasts languages such java in objects chucked around reference semantics instead.

in fact, 1 could argue passage doesn't apply code @ all, because reference not "object".


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