C++ Conditional Operator

Question

I once seen a -wired- operator in C++ which assigns value if greater than..
it was a combination of ? , < and =

eg let x = value if value is greater than x

I x=(x<value)x:value x=(x<value)x:value

It was some sort of x<?=value

But I can not remember it exactly, and can not find it online... Can some one remind me of it?

Thanks,

Answer 1

There is no operator that assigns variables based on their relative values.

However, there is the ?: operator:

x = value > x ? value : x;

If you read it out loud from left to right, it makes sense.

Answer 2

gcc has -- in version 3.3.6 at least! -- a gcc-specific language extension providing specialized operators for implementing min and max. Perhaps this is what you are thinking of?

Minimum and Maximum Operators in C++

I don't have gcc handy to test it with, but it might have an updating form, too.

Answer 3

怎么样：

(x<value) || (x=value)

Answer 4

你在想三元运算符吗？

result = a > b ? x : y;

Answer 5

x = x < value ? 0 : 1;

此函数将x设置为0是x <值，否则为1。

Answer 6

it's a more convenient version of an if statement that is used for assignment

int x = (some bool) ? trueval : falseval;

this is roughly what it means, when the bool is evaluated it either gets the trueval or falseval depending on the outcome, it's easier than saying

int x;
if (someval)
    x = trueval;
else
    x = falseval;

Answer 7

I suspect what you're thinking of is a gcc extension ¹ that lets you leave out the middle operand to the conditional operator, so (for example):

a = b ? b : c;

can be written as:

a = b ?: c;

¹ Despite the '2.95.3' in the URL, I'm not aware of a newer version of the linked page. If somebody is, please feel free to point it out (or edit it in).