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Why would a language NOT use Short-circuit evaluation? Are there any benefits of not using it?
I see that it could lead to some performances issues... is that true? Why?
Related question : Benefits of using short-circuit evaluation
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Disadvantages Of Short-Circuit Evaluation:Code execution becomes less efficient with short-circuited execution paths because in some compilers the new checks for short-circuits are extra execution cycles in themselves.
Short-circuit evaluation, minimal evaluation, or McCarthy evaluation (after John McCarthy) is the semantics of some Boolean operators in some programming languages in which the second argument is executed or evaluated only if the first argument does not suffice to determine the value of the expression: when the first ...
The logical AND operator performs short-circuit evaluation: if the left-hand operand is false, the right-hand expression is not evaluated. The logical OR operator also performs short-circuit evaluation: if the left-hand operand is true, the right-hand expression is not evaluated.
The advantages of C#'s short-circuit evaluation. There are two benefits to the short-circuit behaviour of the && and || operators. It makes our true/false conditions more efficient since not every expression has to be evaluated. And short-circuiting can even prevent errors because it skips part of the code.
Reasons NOT to use short-circuit evaluation:
Because it will behave differently and produce different results if your functions, property Gets or operator methods have side-effects. And this may conflict with: A) Language Standards, B) previous versions of your language, or C) the default assumptions of your languages typical users. These are the reasons that VB has for not short-circuiting.
Because you may want the compiler to have the freedom to reorder and prune expressions, operators and sub-expressions as it sees fit, rather than in the order that the user typed them in. These are the reasons that SQL has for not short-circuiting (or at least not in the way that most developers coming to SQL think it would). Thus SQL (and some other languages) may short-circuit, but only if it decides to and not necessarily in the order that you implicitly specified.
I am assuming here that you are asking about "automatic, implicit order-specific short-circuiting", which is what most developers expect from C,C++,C#,Java, etc. Both VB and SQL have ways to explicitly force order-specific short-circuiting. However, usually when people ask this question it's a "Do What I Meant" question; that is, they mean "why doesn't it Do What I Want?", as in, automatically short-circuit in the order that I wrote it.
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One benefit I can think of is that some operations might have side-effects that you might expect to happen.
Example:
if (true || someBooleanFunctionWithSideEffect()) { ... } But that's typically frowned upon.
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