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POBenefits of using short-circuit evaluation
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copied!<pre><code>boolean a = false, b = true; if ( a && b ) { ... }; </code></pre> <p>In most languages, <code>b</code> will not get evaluated because <code>a</code> is false so <code>a && b</code> cannot be true. My question is, wouldn't short circuiting be slower in terms of architecture? In a pipeline, do you just stall while waiting to get the result of a to determine if b should be evaluated or not? Would it be better to do nested ifs instead? Does that even help?</p> <p>Also, does anyone know what short-circuit evaluation is typically called? This question arose after I found out that my programming friend had never heard of short-circuit evaluation and stated that it is not common, nor found in many languages, and is inefficient in pipeline. I am not certain about the last one, so asking you folks!</p> <p>Okay, I think a different example to perhaps explain where my friend might be coming from. He believes that since evaluating a statement like the following in parallel:</p> <pre><code>(a) if ( ( a != null ) && ( a.equals(b) ) ) { ... } </code></pre> <p>will crash the system, an architecture that doesn't have short-circuiting (and thereby not allowing statements like the above) would be faster in processing statements like these:</p> <pre><code>(b) if ( ( a == 4 ) && ( b == 5 ) ) </code></pre> <p>since if it couldn't do (a) in parallel, it can't do (b) in parallel. In this case, a language that allows short-circuiting is slower than one that does not.</p> <p>I don't know if that's true or not.</p> <p>Thanks</p>

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