But it works only from inside out. The code outside of the function doesn’t see its local variables. A function can return a value. If it doesn’t, then its result is undefined. To make the code clean and easy to understand, it’s recommended to use mainly local variables and parameters in the function, not outer variables. It is always easier to understand a function which gets parameters.
Caution. This function internally performs an eval() and as such has the same security issues as eval().Additionally it has bad performance and memory usage characteristics. If you are using PHP 5.3.0 or newer a native anonymous function should be used instead.
In an HTML page, PHP code is enclosed within special PHP tags. When a visitor opens the page, the server processes the PHP code and then sends the output (not the PHP code itself) to the visitor's browser. Actually it is quite simple to integrate HTML and PHP. A PHP script can be treated as an HTML page, with bits of PHP inserted here and there. Anything in a PHP script that is not contained.
Anonymous functions. Anonymous functions, also known as closures, allow the creation of functions which have no specified name.They are most useful as the value of callback parameters, but they have many other uses. Anonymous functions are implemented using the Closure class.
Strict typing. By default, PHP will coerce values of the wrong type into the expected scalar type if possible. For example, a function that is given an integer for a parameter that expects a string will get a variable of type string. It is possible to enable strict mode on a per-file basis.
Returns a reference to the Function.prototype object. The Function.prototype object allows adding properties and methods to the Function object that can be used with instances of the Function object, like any predefined property or method. The prototype property is static, it cannot be accessed from an instance of the Function object, only Function.prototype is allowed.
NOTE: Functions should be specified in a script in the head section of an HTML document because a script placed in the head section of a webpage will be executed when it is called, or when certain events are triggered such as the clicking of a button or when a form is submitted. Using parameters. Parameters are variables placed inside the parentheses of a function which are used by the code.
Here the value of this inside makeUser() is undefined, because it is called as a function, not as a method with “dot” syntax. The value of this is one for the whole function, code blocks and object literals do not affect it. So ref: this actually takes current this of the function.