what is the use of returning "const & "from a function in C++ ?? Is it used
somewhere at all ??
thank you,
Ranjan.
1  1419 
* maadhuu: what is the use of returning "const & "from a function in C++ ??
What's with the double question mark?
Anyway, re the question, a reference means this is an object that exists
somewhere (not a copy), and const prevents the client code from calling
non-const member functions or directly modifying data members.
Both are guarantees: the existence guarantee is a guarantee the function gives
the client code, so that no checking of existence is needed, and the constness
is a guarantee the function gives about the object.
Is it used somewhere at all ??
Yes. A simple example is a singleton function returning a reference to a
static object. A perhaps less simple, but more often occurring, example, is
the 'at' or operator[] member function of a container such as std::vector.
--
A: Because it messes up the order in which people normally read text.
Q: Why is it such a bad thing?
A: Top-posting.
Q: What is the most annoying thing on usenet and in e-mail? This thread has been closed and replies have been disabled. Please start a new discussion. Similar topics | |
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