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copied!<p>Honestly, in most cases you want to use the if chains because they're more clear to a reader. There are a few exceptions, but not many.</p> <p>Often if your code is awkward, your fundamental approach is wrong. Try this:</p> <pre><code>function validate() { errs = []; // ... if (!txt.length) { errs.push("Must have text, man!"); } // ... return errs.join("<BR>"); } </code></pre> <p>It bears mentioning that strings are immutable in Javascript. If you += on strings, you're creating a lot of intermediary strings, which can slow down performance.</p> <p>E.G.</p> <pre><code>var msg = "Tom"; msg += ", Brad"; msg += ", Sam"; msg += ", Rick"; </code></pre> <p>This ends up creating the following strings in memory:</p> <pre><code>"Tom" "Brad" "Sam" "Rick" "Tom, Brad" "Tom, Brad, Sam" "Tom, Brad, Sam, Rick" </code></pre> <p>Where as the following:</p> <pre><code>var msg = ["Tom", "Brad", "Sam", "Rick"]; var msg = msg.join(", "); </code></pre> <p>creates the following in memory:</p> <pre><code>"Tom" "Brad" "Sam" "Rick" "Tom, Brad, Sam, Rick" </code></pre> <p>Wouldn't make a big difference in this case, most likely, but it's good to get into the habit of creating arrays of strings and using the join method. In larger text manipulation/generation problems, it can cause a huge slowdown.</p> <p>EDIT:</p> <p>If the calling function needs to check for the presence or absence of errors, you can always do an if on the <code>.length</code> of the returned string. If you want to be more explicit, you can always do this:</p> <pre><code>if (!errs.length) { return null; // or false, or a constant... } return errs.join("<BR>"); </code></pre> <p>and then add a check in your calling code (<code>=== null</code>, etc.)</p>

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