Short-Circuit Evaluation: When Should You Use `||` Over `|`?

Short-Circuit Evaluation: Understanding the Difference Between || and |

In programming, we often utilize logical operators such as || (OR) and | (bitwise OR) to evaluate boolean expressions. While both operators perform the logical OR operation, there is a crucial distinction that determines why we typically favor || over |.

The key difference lies in "short-circuit evaluation." When using ||, if the left-hand operand is true, the right-hand operand is not evaluated; similarly, if the left-hand operand is false when using &&, the right-hand operand is not evaluated.

For instance, consider the following code snippets using ||:

if(true || true)  // pass
if(true || false) // pass
if(false || true)  // pass
if(false || false) // no pass

In all cases, the left-hand operand is evaluated first. If it is true, the right-hand operand is not evaluated. Therefore, the code executes efficiently, avoiding unnecessary computations.

In contrast, when using |, both operands are always evaluated:

if(true | true)  // pass
if(true | false) // pass
if(false | true)  // pass
if(false | false) // no pass

This can lead to performance issues, especially when dealing with computationally expensive expressions. Therefore, short-circuit evaluation is highly beneficial for optimization.

Other key advantages of short-circuiting include:

• Null Reference Checks: It allows for safe null reference checks without triggering NullPointerExceptions.
• Conditional Debugging: By eliminating the evaluation of unnecessary expressions, debugging can become more efficient and easier.

Remember, || and | can both be used for logical OR operations, but the benefits of short-circuiting evaluation generally make || the preferred choice. It promotes code efficiency, reduces performance overhead, and facilitates more reliable programming.

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