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<qhelp>

<overview>

<p>

Calling the builtin methods

<code>String.prototype.split</code> and

<code>String.prototype.replace</code> with a string as the first

argument makes the methods search for that exact string. Providing a

regular expression instead of the string makes the methods perform a

regular expression search.

</p>

<p>

Calling the methods with a string that has the format of a

regular expression is likely a mistake because the methods will not

convert the string to a regular expression.

</p>

</overview>

<recommendation>

<p>

Call <code>String.prototype.split</code> and

<code>String.prototype.replace</code> with a regular expression as the

first argument unless you want an exact search.

</p>

</recommendation>

<example>

<p>

The following code snippet shows a call to

<code>String.prototype.replace</code>. The purpose of the call is to

remove all characters that are not alphanumeric.

</p>

<sample language="javascript">

var cleaned = input.replace("[^a-zA-Z0-9]+", "");

</sample>

<p>

Unfortunately, the first argument is a string and not a

regular expression, so the call will only remove the

first substring that is exactly "<code>[^a-zA-Z0-9]+</code>".

</p>

<p>

Instead, the first argument should be a regular expression

with the <code>global</code> flag set:

</p>

<sample language="javascript">

var cleaned = input.replace(/[^a-zA-Z0-9]+/g, "");

</sample>

</example>

<references>

<li>Mozilla Developer Network: <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/String/split">String.prototype.split</a></li>

<li>Mozilla Developer Network: <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/String/replace">String.prototype.replace</a></li>

</references>

</qhelp>