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<qhelp>

<overview>

<p>

Referencing an otherwise undeclared global variable in a module that exports

a definition of the same name is confusing and may indicate a bug.

</p>

</overview>

<recommendation>

<p>

If the global variable reference is intentional, consider adding a JSLint

<code>/*global ...*/</code> directive or an externs declaration to declare the variable.

</p>

<p>

If the global variable reference is unintentional, qualifying the reference

with <code>exports</code> will make it refer to the exported definition instead.

</p>

</recommendation>

<example>

<p>

In the following example, the module exports two functions <code>checkOne</code>

and <code>checkList</code>. The latter is also stored in a variable of the same name

that is local to the module, but the former is not. Hence the call <code>checkOne(xs[i])</code>

on line 7 does not refer to the function defined on line 1, but to an otherwise undeclared

global variable also called <code>checkOne</code>.

</p>

<sample src="examples/MissingExports.js" />

<p>

Assuming that the intention is to call the <code>checkOne</code> function defined on line 1,

the call should be qualified with <code>exports</code> like this:

</p>

<sample src="examples/MissingExportsGood.js" />

</example>

<references>

<li>Node.js: <a href="https://nodejs.org/api/modules.html">Modules</a>.</li>

<li>JSLint Help: <a href="http://www.jslint.com/help.html">JSLint Directives</a>.</li>

<li>Closure Compiler: <a href="https://developers.google.com/closure/compiler/docs/api-tutorial3">Advanced Compilation and Externs</a>.</li>

</references>

</qhelp>