PHP Encapsulation

The wrapping up of data and methods into a single unit (called class) is known as encapsulation. Encapsulation is a protection mechanism for the data members and methods present inside the class. In the encapsulation technique, we are restricting the data members from access to outside world end-user.

In PHP, encapsulation utilized to make the code more secure and robust. Using encapsulation, we are hiding the real implementation of data from the user and also does not allow anyone to manipulate data members except by calling the desired operation.


Variable pools PHP

Variable pools are functional groupings of variables within Service Manager. There are currently four variable pools


A global variable is visible to the entire system. It begins with $G. or $lo..


A local variable is only visible to the RAD application in which it was defined. It begins with $L..


A parameter variable is defined on a parameter command panel. It may contain a value passed in from another application. By convention, parameter variables are written in uppercase letters, such as $PHASE or $GROUP.LIST. Parameter variables are invisible to the debugger.


A thread variable is only visible to the thread in which it was defined. The same variable in different threads has different values, even when the threads are spawned by the same parent.

Cross-Origin Resource Sharing

Cross-Origin Resource Sharing (CORS) is a mechanism that uses additional HTTP headers to tell browsers to give a web application running at one origin, access to selected resources from a different origin. A web application executes a cross-origin HTTP request when it requests a resource that has a different origin (domain, protocol, or port) from its own.

Expectations php

Expectations are a backwards compatible enhancement to the older assert() function. Expectation allows for zero-cost assertions in production code, and provides the ability to throw custom exceptions when the assertion fails. assert() is now a language construct, where the first parameter is an expression as compared to being a string or Boolean to be tested.


IntlChar provides access to a number of utility methods that can be used to access information about Unicode characters.

The methods and constants adhere closely to the names and behavior used by the underlying ICU library.

Unicode codepoint escape syntax

Despite the wide and increasing adoption of Unicode (and UTF-8 in particular) in PHP applications, PHP does not yet have a Unicode codepoint escape syntax in string literals, unlike many other languages. This is unfortunate, as in many cases it can be useful to specify Unicode codepoints by number, rather than using the codepoint directly. For example, say you wish to output the UTF-8 encoded Unicode codepoint U+202E RIGHT-TO-LEFT OVERRIDE in order to display text right-to-left. You could embed it in source code directly, but it is an invisible character and would display the rest of the line of code (or indeed entire program) in reverse!

The solution is to add a Unicode codepoint escape sequence syntax to string literals. This would mean you could produce U+202E like so: