Welcome to ShenZhenJia Knowledge Sharing Community for programmer and developer-Open, Learning and Share
menu search
person
Welcome To Ask or Share your Answers For Others

Categories

In C++, pre-increment operator gives lvalue because incremented object itself is returned, not a copy. But in C, it gives rvalue. Why?

See Question&Answers more detail:os

与恶龙缠斗过久,自身亦成为恶龙;凝视深渊过久,深渊将回以凝视…
thumb_up_alt 0 like thumb_down_alt 0 dislike
429 views
Welcome To Ask or Share your Answers For Others

1 Answer

C doesn't have references. In C++ ++i returns a reference to i (lvalue) whereas in C it returns a copy(incremented).

C99 6.5.3.1/2

The value of the operand of the pre?x ++ operator is incremented. The result is the new value of the operand after incrementation. The expression ++Eis equivalent to (E+=1).

‘‘value of an expression’’ <=> rvalue

However for historical reasons I think "references not being part of C" could be a possible reason.


与恶龙缠斗过久,自身亦成为恶龙;凝视深渊过久,深渊将回以凝视…
thumb_up_alt 0 like thumb_down_alt 0 dislike
Welcome to ShenZhenJia Knowledge Sharing Community for programmer and developer-Open, Learning and Share
...