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diff --git a/files/fa/web/javascript/reference/errors/too_much_recursion/index.html b/files/fa/web/javascript/reference/errors/too_much_recursion/index.html deleted file mode 100644 index 02a8d54c45..0000000000 --- a/files/fa/web/javascript/reference/errors/too_much_recursion/index.html +++ /dev/null @@ -1,114 +0,0 @@ ---- -title: 'InternalError: too much recursion' -slug: Web/JavaScript/Reference/Errors/Too_much_recursion -translation_of: Web/JavaScript/Reference/Errors/Too_much_recursion ---- -<div>{{jsSidebar("Errors")}}</div> - -<h2 id="Message">Message</h2> - -<pre class="syntaxbox">Error: Out of stack space (Edge) -InternalError: too much recursion (Firefox) -RangeError: Maximum call stack size exceeded (Chrome) -</pre> - -<h2 id="Error_type">Error type</h2> - -<p>{{jsxref("InternalError")}}.</p> - -<h2 id="What_went_wrong">What went wrong?</h2> - -<p>A function that calls itself is called a <em>recursive function</em>. Once a condition is met, the function stops calling itself. This is called a <em>base case</em>.</p> - -<p>In some ways, recursion is analogous to a loop. Both execute the same code multiple times, and both require a condition (to avoid an infinite loop, or rather, infinite recursion in this case). <span class="seoSummary">When there are too many function calls, or a function is missing a base case, JavaScript will throw this error.</span></p> - -<h2 id="Examples">Examples</h2> - -<p>This recursive function runs 10 times, as per the exit condition.</p> - -<pre class="brush: js">function loop(x) { - if (x >= 10) // "x >= 10" is the exit condition - return; - // do stuff - loop(x + 1); // the recursive call -} -loop(0);</pre> - -<p>Setting this condition to an extremely high value, won't work:</p> - -<pre class="brush: js example-bad">function loop(x) { - if (x >= 1000000000000) - return; - // do stuff - loop(x + 1); -} -loop(0); - -// InternalError: too much recursion</pre> - -<p>This recursive function is missing a base case. As there is no exit condition, the function will call itself infinitely.</p> - -<pre class="brush: js example-bad">function loop(x) { - // The base case is missing - -loop(x + 1); // Recursive call -} - -loop(0); - -// InternalError: too much recursion</pre> - -<h3 id="Class_error_too_much_recursion">Class error: too much recursion</h3> - -<pre class="brush: js example-bad">class Person{ - constructor(){} - set name(name){ - this.name = name; // Recursive call - } -} - - -const tony = new Person(); -tony.name = "Tonisha"; // InternalError: too much recursion -</pre> - -<p>When a value is assigned to the property name (this.name = name;) JavaScript needs to set that property. When this happens, the setter function is triggered.</p> - -<pre class="brush: js example-bad">set name(name){ - this.name = name; // Recursive call -} -</pre> - -<div class="note"> -<p>In this example when the setter is triggered, it is told to do the same thing again: <em>to set the same property that it is meant to handle.</em> This causes the function to call itself, again and again, making it infinitely recursive.</p> -</div> - -<p>This issue also appears if the same variable is used in the getter.</p> - -<pre class="brush: js example-bad">get name(){ - return this.name; // Recursive call -} -</pre> - -<p>To avoid this problem, make sure that the property being assigned to inside the setter function is different from the one that initially triggered the setter.The same goes for the getter.</p> - -<pre class="brush: js">class Person{ - constructor(){} - set name(name){ - this._name = name; - } - get name(){ - return this._name; - } -} -const tony = new Person(); -tony.name = "Tonisha"; -console.log(tony); -</pre> - -<h2 id="See_also">See also</h2> - -<ul> - <li>{{Glossary("Recursion")}}</li> - <li><a href="/en-US/docs/Web/JavaScript/Guide/Functions#Recursion">Recursive functions</a></li> -</ul> |