(window.webpackJsonp=window.webpackJsonp||[]).push([[2429],{2836:function(t,s,a){"use strict";a.r(s);var n=a(31),e=Object(n.a)({},(function(){var t=this,s=t.$createElement,a=t._self._c||s;return a("ContentSlotsDistributor",{attrs:{"slot-key":t.$parent.slotKey}},[a("h1",{attrs:{id:"closure"}},[a("a",{staticClass:"header-anchor",attrs:{href:"#closure"}},[t._v("#")]),t._v(" Closure")]),t._v(" "),a("h2",{attrs:{id:"basic-usage-of-a-closure"}},[a("a",{staticClass:"header-anchor",attrs:{href:"#basic-usage-of-a-closure"}},[t._v("#")]),t._v(" Basic usage of a closure")]),t._v(" "),a("p",[t._v("A "),a("strong",[t._v("closure")]),t._v(" is the PHP equivalent of an anonymous function, eg. a function that does not have a name. Even if that is technically not correct, the behavior of a closure remains the same as a function's, with a few extra features.")]),t._v(" "),a("p",[t._v("A closure is nothing but an object of the Closure class which is created by declaring a function without a name. 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One of them is "),a("code",[t._v("bindTo")]),t._v(", which, given a closure, will return a new one that is bound to a given object. 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You get a fatal error indicating that you do not have access to this property. Indeed, even if the closure has been bound to the object, the scope in which the closure is invoked is not the one needed to have that access. That is what the second argument of "),a("code",[t._v("bindTo")]),t._v(" is for.")]),t._v(" "),a("p",[t._v("The only way for a property to be accessed if it's "),a("code",[t._v("private")]),t._v(" is that it is accessed from a scope that allows it, ie. the class's scope. In the just previous code example, the scope has not been specified, which means that the closure has been invoked in the same scope as the one used where the closure has been created. Let's change that:")]),t._v(" "),a("div",{staticClass:"language-php extra-class"},[a("pre",{pre:!0,attrs:{class:"language-php"}},[a("code",[a("span",{pre:!0,attrs:{class:"token php language-php"}},[a("span",{pre:!0,attrs:{class:"token delimiter important"}},[t._v("<?php")]),t._v("\n\n"),a("span",{pre:!0,attrs:{class:"token variable"}},[t._v("$myClosure")]),t._v(" "),a("span",{pre:!0,attrs:{class:"token operator"}},[t._v("=")]),t._v(" "),a("span",{pre:!0,attrs:{class:"token keyword"}},[t._v("function")]),a("span",{pre:!0,attrs:{class:"token punctuation"}},[t._v("(")]),a("span",{pre:!0,attrs:{class:"token punctuation"}},[t._v(")")]),t._v(" "),a("span",{pre:!0,attrs:{class:"token punctuation"}},[t._v("{")]),t._v("\n    "),a("span",{pre:!0,attrs:{class:"token keyword"}},[t._v("echo")]),t._v(" "),a("span",{pre:!0,attrs:{class:"token variable"}},[t._v("$this")]),a("span",{pre:!0,attrs:{class:"token operator"}},[t._v("->")]),a("span",{pre:!0,attrs:{class:"token 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For example, a closure created inside a method's class which is invoked in an object context will have the same scope as the method's:")]),t._v(" "),a("div",{staticClass:"language-php extra-class"},[a("pre",{pre:!0,attrs:{class:"language-php"}},[a("code",[a("span",{pre:!0,attrs:{class:"token php language-php"}},[a("span",{pre:!0,attrs:{class:"token delimiter important"}},[t._v("<?php")]),t._v("\n\n"),a("span",{pre:!0,attrs:{class:"token keyword"}},[t._v("class")]),t._v(" "),a("span",{pre:!0,attrs:{class:"token class-name-definition class-name"}},[t._v("MyClass")]),t._v("\n"),a("span",{pre:!0,attrs:{class:"token punctuation"}},[t._v("{")]),t._v("\n    "),a("span",{pre:!0,attrs:{class:"token keyword"}},[t._v("private")]),t._v(" "),a("span",{pre:!0,attrs:{class:"token variable"}},[t._v("$property")]),a("span",{pre:!0,attrs:{class:"token punctuation"}},[t._v(";")]),t._v("\n\n    "),a("span",{pre:!0,attrs:{class:"token keyword"}},[t._v("public")]),t._v(" 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