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46 lines
1.1 KiB
XML
46 lines
1.1 KiB
XML
<!DOCTYPE qhelp PUBLIC
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"-//Semmle//qhelp//EN"
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"qhelp.dtd">
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<qhelp>
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<overview>
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<p>
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The <code>delete</code> operator should only be used to delete properties from objects. Using it
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to delete variables makes code hard to maintain and will break in strict mode.
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</p>
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</overview>
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<recommendation>
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<p>
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If the variable you are deleting is a global variable, this is a sign that your code relies too
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much on global state. Try encapsulating this global state by means of one of the module patterns
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introduced in <i>JavaScript: The Good Parts</i>.
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</p>
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</recommendation>
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<example>
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<p>
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In the following code snippet, <code>delete</code> is used to clean up the global <code>cache</code>
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variable used by function <code>get</code>.
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</p>
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<sample src="examples/DeleteVar.js" />
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<p>
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It would be clearer to wrap the whole module into a closure like this (which also avoids exposing
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function <code>compute</code> to the outside world):
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</p>
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<sample src="examples/DeleteVarGood.js" />
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</example>
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<references>
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<li>JSLint Error Explanations: <a href="http://jslinterrors.com/only-properties-should-be-deleted">Only properties should be deleted</a>.</li>
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</references>
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</qhelp>
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