CODEWITHSUNDEEP
javaternary-operator
chama
chama

Reputation: 6163

Assignment as part of ternary if

I found the following snippet in our code base. This is code that is widely used and hasn't caused any issues, and I can't figure out why.

element = someBoolean ?
            element = parentElement :
            element;

Shouldn't the second line be resetting element to an empty value or something after it is set to parentElement

ETA: I am wondering what the return value of the element = parentElement clause would be because it didn't seem like there was any return value over there. I forgot that there is a concept of multiple assignments in java, so element would just be set twice.

Upvotes: 1

Views: 56

Answers (2)

Florian Schaetz
Florian Schaetz

Reputation: 10652

The assignment is quite useless, since your code can be written as...

element = someBoolean ?
            parentElement:
            element;

Only in your code, you do not return parentElement immediately, but first set element to parentElement and then element to element.

Upvotes: 3

GriffeyDog
GriffeyDog

Reputation: 8376

Shouldn't the second line be resetting element to an empty value or something after it is set to parentElement

I don't know why you would think that. The purpose of the entire statement is to potentially reassign element to parentElement. The statement is equivalent to:

element = someBoolean ?
            parentElement:
            element;

This is because an assignment statement (element = parentElement) has a value of the RHS (i.e. parentElement). I would simply write it this way, though:

if (someBoolean) {
    element = parentElement;
}

Upvotes: 8

Related Questions