Beta testing for PHP 8 has begun

Introduced the first beta release of the new branch of the PHP 8 programming language. The release is scheduled for November 26. At the same time, corrective releases of PHP 7.4.9, 7.3.21 and
7.2.33, in which accumulated errors and vulnerabilities have been fixed.

Key innovations PHP 8:

• Enabling the JIT compiler, whose implementation will increase performance.
• Support named function arguments, allowing values to be passed to a function bound by names, meaning arguments can be passed in any order and optional arguments can be defined. For example, "array_fill(start_index: 0, num: 100, value: 50)".
• When calling methods are allowed using the "?" operator, which allows the invocation to be initiated only if the method exists, thus avoiding unnecessary checks for a "null" return value. For example, "$dateAsString = $booking->getStartDate()?->asDateTimeString()";
• Support union types, defining collections of two or more types (for example, 'public function foo(Foo|Bar $input): int|float;').
• Support attributes (annotations) that allow binding metadata (e.g., type information) to classes without using the Docblock syntax.
• Support for expressions match, which unlike switch can return values, support condition combination, use strict type comparison, and do not require specifying "break".

  $result = match($input) {
  0 => "hello",
  '1', '2', '3' => "world",
  };
• Shortened syntax for class definitions, allowing the constructor and property definitions to be combined.
• A new return type — static.
• The new type — mixed, which can be used to define a function's acceptance of parameters of different types.
• Expression throw for handling exceptions.
• WeakMap for creating objects that can be garbage collected (for example, for storing optional caches).
• Possibility of using the expression '::class' for objects (similar to calling get_class()).
• Possibility of definitions in the catch block of exceptions not bound to variables.
• Possibility of leaving a comma after the last element in a function parameter list.
• better matches the browser interface. Support for AcroForm (form filling will be included later, activated via the setting pdfjs.renderInteractiveForms) has been added. Stringable to identify any string types or data that can be converted to a string (for which the method __toString() is available).
• A new function str_contains(), a simplified equivalent of strpos for determining substring presence, as well as the functions str_starts_with() and str_ends_with() for checking matches at the beginning and end of a string.
• A function has been added fdiv(), which performs division without throwing an error in the case of division by zero.
• Modified the logic for string concatenation. For example, the expression 'echo "sum: " . $a + $b' was previously interpreted as 'echo ("sum: " . $a) + $b', whereas in PHP 8 it will be processed as 'echo "sum: " . ($a + $b)'.
• The protection against the use of GPL wrappers to bind proprietary drivers to kernel components exported only for GPL-licensed modules has been tightened. The TAINT_PROPRIETARY_MODULE flag is now inherited in all modules that import symbols from modules with this flag. If a GPL module attempts to import symbols from a non-GPL module, that GPL module will inherit the TAINT_PROPRIETARY_MODULE label and will not be able to access kernel components available only to GPL-licensed modules, even if the module previously imported symbols from the 'gplonly' category. The reverse block (exporting only EXPORT_SYMBOL_GPL in modules that imported EXPORT_SYMBOL_GPL), which could disrupt the operation of proprietary drivers, is not implemented (only the proprietary module flag is inherited, but not GPL binding). checks for arithmetic and bitwise operations, for example, the expressions '[] % [42]' and '$object + 4' will result in an error.
• Implemented a stable sorting algorithm, in which the order of identical values is preserved across different runs.

Source: opennet.ru