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.

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:

Array constants can now be defined using the define() function. In PHP 5.6, they could only be defined using const keyword.

<?php
   //define a array using define function
   define('languages', [
      'PHP',
      'JSP',
      'ASP'
   ]);
   print(languages[0]);
?>

You can use the PHP newline characters \n or \r\n to create a new line inside the source code. However, if you want the line breaks to be visible in the browser too, you can use the PHP nl2br() function which inserts HTML line breaks before all newlines in a string.

Use the php constant PHP_EOL to print the correct end of line symbol no matter what system you’re on.

<?php 
    print "Hello There," . PHP_EOL . "Welcome to PHPCodez"; 
 ?>

Type declarations are what allows the function to require certain types of parameters at call time. There are two types Scalar type declarations: one is coercive or you can say it default and other is strict.

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