# Conditional operator

The conditional operator is supported in many programming languages. This term usually refers to ?: as in C, C++, C#, and JavaScript. However, in Java, this term can also refer to && and ||.

## && and ||

In some programming languages, e.g. Java, the term conditional operator refers to short circuit boolean operators && and ||. The second expression is evaluated only when the first expression is not sufficient to determine the value of the whole expression.

### Difference from bitwise operator

& and | are bitwise operators that occur in many programming languages. The major difference is that bitwise operations operate on the individual bits of a binary numeral, whereas conditional operators operate on logical operations. Additionally, expressions before and after a bitwise operator are always evaluated.
If expression 1 is true, expressions 2 and 3 are NOT checked.
This checks expressions 2 and 3, even if expression 1 is true.
Short circuit operators can reduce run times by avoiding unnecessary calculations. They can also avoid Null Exceptions when expression 1 checks whether an object is valid.

### Usage in Java

In most programming languages, ?: is called the conditional operator. It is a type of ternary operator. However, ternary operator in most situations refers specifically to ?: because it is the only operator that takes three operands.

### Regular usage of "?:"

?: is used in conditional expressions. Programmers can rewrite an if-then-else expression in a more concise way by using the conditional operator.

#### Syntax

condition: An expression which is evaluated as a boolean value.
expression 1, expression 2: Expressions with values of any type.
If the condition is evaluated to true, the expression 1 will be evaluated. If the condition is evaluated to false, the expression 2 will be evaluated.
It should be read as: "If condition is true, assign the value of expression 1 to result. Otherwise, assign the value of expression 2 to result."

#### Association property

The conditional operator is right-associative, meaning that operations are grouped from right to left. For example, an expression of the form a ? b : c ? d : e is evaluated as a ? b : (c ? d : e).

#### Examples by languages
##### Java

In this example, because someCondition is true, this program prints "1" to the screen. Use the ?: operator instead of an if-then-else statement if it makes your code more readable; for example, when the expressions are compact and without side-effects (such as assignments).

##### C++

There are several rules that apply to the second and third operands in C++:
* If both operands are of the same type, the result is of that type
* If both operands are of arithmetic or enumeration types, the usual arithmetic conversions (covered in Standard Conversions) are performed to convert them to a common type
* If both operands are of pointer types or if one is a pointer type and the other is a constant expression that evaluates to 0, pointer conversions are performed to convert them to a common type
* If both operands are of reference types, reference conversions are performed to convert them to a common type
* If both operands are of type void, the common type is type void
* If both operands are of the same user-defined type, the common type is that type.

##### C#

There are several rules that apply to the second and third operands x and y in C#:
* If x has type X and y has type Y:
* If an implicit conversion exists from X to Y but not from Y to X, Y is the type of the conditional expression.
* If an implicit conversion exists from Y to X but not from X to Y, X is the type of the conditional expression.
* Otherwise, no expression type can be determined, and a compile-time error occurs.
* If only one of x and y has a type, and both x and y are implicitly convertible to that type, that type is the type of the conditional expression.
* Otherwise, no expression type can be determined, and a compile-time error occurs.

##### JavaScript

The conditional operator of JavaScript is compatible with the following browsers:
Chrome, Edge, Firefox (1), Internet Explorer, Opera, Safari, Android webview, Chrome for Android, Edge Mobile, Firefox for Android (4), Opera for Android, Safari on IOS, Samsung Internet, Node.js.

### Special usage in conditional chain

The ternary operator is right-associative, which means it can be "chained" in the following way, similar to an if ... else if ... else if ... else chain.

#### Examples by languages
##### C/C++
### Special usage in assignment expression

the conditional operator can yield a L-value in C/C++ which can be assigned another value, but the vast majority of programmers consider this extremely poor style, if only because of the technique's obscurity.