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    <p>As I have been finding out, a lot of these helper functions are really necessary because PHP isn't strongly typed. I posted a <a href="https://stackoverflow.com/questions/3295128/is-this-an-ok-test-to-see-if-a-variable-is-set">similar question</a> (although not <em>that</em> similar) about isset earlier this week. One thing to note is that <strong>PHP will change your string to its integer value</strong> for comparisons during some instances (when there are mixed types). This can't be overlooked. I think this is a strong case for <code>is_numeric</code></p> <p>from <a href="http://php.net/manual/en/language.operators.comparison.php" rel="nofollow noreferrer">PHP Manual</a></p> <blockquote> <p>If you compare a number with a string or the comparison involves numerical strings, then each string is converted to a number and the comparison performed numerically. These rules also apply to the switch statement. The type conversion does not take place when the comparison is === or !== as this involves comparing the type as well as the value.</p> </blockquote> <p>Another thing to think about is that "what is 0" in PHP. It means a lot. It's not always numeric. It may be a numeric string, boolean false, integer, etc... This is why those helper functions exist.</p> <p>To add to my answer:</p> <p>change your example:</p> <pre><code>$whatami='beast'; ($whatami&lt;5) ? echo 'less than 5' : echo 'more than 5'; </code></pre> <p>PHP would change 'beast' to its integer equivalent and then do the comparison. This would give unintended results. If you really wanted something similar, you'd have to wrap it in another conditional:</p> <pre><code>$whatami='beauty'; if(is_numeric($whatami){ ($whatami&lt;5) ? echo 'less than 5' : echo 'more than 5'; } else { exit('what, am I not pretty enough for a beast?'); } </code></pre> <p>Then you would get your intended result (as weird as it may be).</p>
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    1. POPHP - usage of is_numeric() necessary, or can use comparison signs work for all positive numeric cases?
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    1. COOK - sorry, I meant to say it's only a check for positive numeric values. (numbers > 0) being the subset of validated variables to take. See comments above!
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    2. COif you already validated or type-cast the variable, and you are certain that it hasn't changed, then you can safely leave out is_numeric for comparisons or absolutely know that the value is numeric. This (kind of) assumes that you already used is_numeric in your code, though. You may still want to use it because if you don't then something could sneak up on you (if you get the number from a DB that's always an INT, what happens when the query fails or returns NULL?)
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