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60 lines
1.5 KiB
XML
60 lines
1.5 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 properties <code>callee</code> and <code>caller</code> of arguments objects as well
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as the properties <code>caller</code> and <code>arguments</code> of function objects are
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not available in strict-mode code, and any attempt to access them will result in a runtime
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error.
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</p>
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</overview>
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<recommendation>
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<p>
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Instead of using <code>arguments.callee</code>, you can refer to the enclosing function by
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its name (possibly giving it a name first if it is an anonymous function expression).
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Uses of the other properties can often be eliminated by refactoring the program.
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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 example, <code>arguments.callee</code> is used to recursively invoke the
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enclosing function, which is anonymous.
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</p>
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<sample language="javascript">
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var o = {
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A: function(x) {
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'use strict';
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if (!(this instanceof arguments.callee))
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return new arguments.callee(x);
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this.x = x;
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}
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};
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</sample>
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<p>
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To avoid this use, the function can be given a name and referred to using that name:
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</p>
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<sample language="javascript">
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var o = {
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A: function A(x) {
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'use strict';
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if (!(this instanceof A))
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return new A(x);
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this.x = x;
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}
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};
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</sample>
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</example>
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<references>
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<li>Mozilla Developer Network: <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Functions_and_function_scope/arguments">arguments</a>.</li>
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</references>
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</qhelp>
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