PHP7.0 and 7.1 Parts new features memo code sharing

The following are some additions to the PHP 7.0 & 7.1 version, respectively.

PHP 7.0

?? Operator

$foo = null; $bar = $foo?? 123;//equivalent to $bar = Isset ($bar)? $bar: 123

Parameter type, return type, and strict mode

In strict mode, the parameter type mismatch throws an error declare (Strict_types=1); function fn (int $a): int{    echo $a;} FN (1.2);

Combining a comparison character

Returns 0 when they are equal;

The former is greater than the latter return 1;
The latter is greater than the former return-1;

Var_dump ($a <=> $b);

$a = 0; $b = "abc"; var_dump ($a <=> $b);//Note that strings are treated as 0 when compared to numbers;

Generator with return value

function Generator () {    yield 1;    Yield 2;    Return "a";} $generator = Generator (), foreach ($generator as $val) {    var_dump ($val);} Var_dump ($generator->getreturn ());

When used without a return value $generator->getReturn() , it is returned null . Also, when the generator does not have the output complete, the use $generator->getReturn() will error.

function Generator () {    yield 1;    Yield 2;    Return "a";} $generator = Generator (), Var_dump ($generator->current ()), Var_dump ($generator->next ()), Var_dump ($generator- >getreturn ()); Error Var_dump ($generator->current ()); Var_dump ($generator->next ());

Defining a constant array

Define (' COLORS ', [' Red ', ' blue ', ' black ']); Echo colors[1];  Red

Multiple use declarations

Use Some\namespace\{classa, ClassB, ClassC as C};use function some\namespace\{fn_a, Fn_b, Fn_c};use const some\namespace\ {Consta, CONSTB, CONSTC};

Array Deconstruction

List ($a, $b) = ["A", "B"];

PHP 7.1

Jit

JIT, just in time. The runtime converts part of the instruction to machine code. There is a high performance boost for compute-intensive applications.

Optional parameter types

function (? string $name) {    var_dump ($name);} The argument type is string or null

Note the difference from the default parameter values:

function (String $name = "Default-name") {    var_dump ($name);}

Array Deconstruction

[$a, $b] = ["A", "B"];

Iterable & Callable Pseudo-class types

Use the callable type to represent the type of the argument that is callable (function, class instance that implements Invoke);

Use the iterable type to restrict the type of the argument to an iterative type (array, class instance that implements the Iterator or traversable interface);

Multiple exception type capture

try {    } catch (Oneexception | Anotherexception $e) {    }