x += i is valid but x = x + i does not compile

Asked Dec 03 '15 at 19:06

Active Dec 03 '15 at 19:06

Viewed 99 times

I have the following Java code:

double i = 4.2;
int x = 42;

x += i;      // A valid statement
x = x + i;   // An invalid statement

x += i seems to give no errors, and sets the value of x to 46, whereas x = x + i (correctly) gives a compilation error:

Error:(30, 15) java: incompatible types: possible lossy conversion from double to int

Clearly there is a lossy conversion in x += i too. Why is that statement valid?

asked Dec 03 '15 at 19:06

John Bupit

6

@rgettman Well done, I couldn't find the duplicate. SO doesn't let you search on `+=` – Peter Lawrey Dec 03 '15 at 19:10
4

Neither could I. Hence, the question. – John Bupit Dec 03 '15 at 19:11
2

To be fair, I have the second most popular answer, and I still could find it. ;) – Peter Lawrey Dec 03 '15 at 19:13
@SotiriosDelimanolis ok, google doesn't like `+=` either. – Peter Lawrey Dec 03 '15 at 19:13
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@PeterLawrey some love for me too! I was the one who marked it first ! :p – StackFlowed Dec 03 '15 at 19:17
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@StackFlowed thank you too. +1 – Peter Lawrey Dec 03 '15 at 19:18
@PeterLawrey I tried using HTML Entity Codes, or in other words, `+=` ... Doesn't work either. =( Apparently SO strips punctuation off of searches, like google does? – CosmicGiant Dec 03 '15 at 19:44

0 Answers0