The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT", "SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this document are to be interpreted as described in RFC 2119.
This specification extends, expands and replaces PSR-12, the extended coding style guide and requires adherence to PSR-1, the basic coding standard.
Like PSR-12, the intent of this specification is to reduce cognitive friction when scanning code from different authors. It does so by enumerating a shared set of rules and expectations about how to format PHP code. This PSR seeks to provide a set that coding style tools can implement, projects can declare adherence to and developers can easily relate to between different projects. When various authors collaborate across multiple projects, it helps to have one set of guidelines to be used among all those projects. Thus, the benefit of this guide is not in the rules themselves but the sharing of those rules.
PSR-12 was accepted in 2019 and since then a number of changes have been made to PHP which have implications for coding style guidelines. Whilst PSR-12 is very comprehensive of PHP functionality that existed at the time of writing, new functionality is very open to interpretation. This PER, therefore, seeks to clarify the content of PSR-12 in a more modern context with new functionality available, make the errata to PSR-12 binding and further update it according to new data and language changes.
Throughout this document, any instructions MAY be ignored if they do not exist in versions of PHP supported by your project.
This example encompasses some rules below as a quick overview:
<?php
declare(strict_types=1);
namespace Vendor\Package;
use Vendor\Package\{ClassA as A, ClassB, ClassC as C};
use Vendor\Package\SomeNamespace\ClassD as D;
use function Vendor\Package\{functionA, functionB, functionC};
use const Vendor\Package\{ConstantA, ConstantB, ConstantC};
class Foo extends Bar implements FooInterface
{
public function sampleFunction(int $a, int $b = null): array
{
if ($a === $b) {
bar();
} elseif ($a > $b) {
$foo->bar($arg1);
} else {
BazClass::bar($arg2, $arg3);
}
}
final public static function bar()
{
// ...
}
}
enum Beep: int
{
case Foo = 1;
case Bar = 2;
public function isOdd(): bool
{
return $this->value() % 2;
}
}Code MUST follow all rules outlined in PSR-1.
The term "StudlyCaps" in PSR-1 MUST be interpreted as PascalCase where the first letter of each word is capitalized including the very first letter.
All PHP files MUST use the Unix LF (linefeed) line ending only.
All PHP files MUST end with a non-blank line, terminated with a single LF.
The closing ?> tag MUST be omitted from files containing only PHP.
There MUST NOT be a hard limit on line length.
The soft limit on line length MUST be 120 characters.
Lines SHOULD NOT be longer than 80 characters; lines longer than that SHOULD be split into multiple subsequent lines of no more than 80 characters each.
There MUST NOT be trailing whitespace at the end of lines.
Blank lines MAY be added to improve readability and to indicate related blocks of code except where explicitly forbidden.
There MUST NOT be more than one statement per line.
Code MUST use an indent of 4 spaces for each indent level, and MUST NOT use tabs for indenting.
All PHP reserved keywords and types [1][2] MUST be in lower case.
Any new types and keywords added to future PHP versions MUST be in lower case.
Short form of type keywords MUST be used i.e. bool instead of boolean,
int instead of integer etc.
Numerous PHP constructs allow a sequence of values to be separated by a comma,
and the final item may have an optional comma. Examples include array key/value pairs,
function arguments, closure use statements, match() statement branches, etc.
If that list is contained on a single line, then the last item MUST NOT have a trailing comma.
If the list is split across multiple lines, then the last item MUST have a trailing comma.
The following are examples of correct comma placement:
function beep(string $a, string $b, string $c)
{
// ...
}
function beep(
string $a,
string $b,
string $c,
) {
// ...
}
$arr = ['a' => 'A', 'b' => 'B', 'c' => 'C'];
$arr = [
'a' => 'A',
'b' => 'B',
'c' => 'C',
];
$result = match ($a) {
'foo' => 'Foo',
'bar' => 'Bar',
default => 'Baz',
};The header of a PHP file may consist of a number of different blocks. If present, each of the blocks below MUST be separated by a single blank line, and MUST NOT contain a blank line. Each block MUST be in the order listed below, although blocks that are not relevant may be omitted.
- Opening
<?phptag. - File-level docblock.
- One or more declare statements.
- The namespace declaration of the file.
- One or more class-based
useimport statements. - One or more function-based
useimport statements. - One or more constant-based
useimport statements. - The remainder of the code in the file.
When a file contains a mix of HTML and PHP, any of the above sections may still be used. If so, they MUST be present at the top of the file, even if the remainder of the code consists of a closing PHP tag and then a mixture of HTML and PHP.
When the opening <?php tag is on the first line of the file, it MUST be on its
own line with no other statements unless it is a file containing markup outside of PHP
opening and closing tags.
Import statements MUST never begin with a leading backslash as they must always be fully qualified.
The following example illustrates a complete list of all blocks:
<?php
/**
* This file contains an example of coding styles.
*/
declare(strict_types=1);
namespace Vendor\Package;
use Vendor\Package\{ClassA as A, ClassB, ClassC as C};
use Vendor\Package\SomeNamespace\ClassD as D;
use Vendor\Package\AnotherNamespace\ClassE as E;
use SomeVendor\Pack\ANamespace\SubNamespace\ClassF;
use function Vendor\Package\{functionA, functionB, functionC};
use function Another\Vendor\functionD;
use const Vendor\Package\{CONSTANT_A, CONSTANT_B, CONSTANT_C};
use const Another\Vendor\CONSTANT_D;
/**
* FooBar is an example class.
*/
class FooBar
{
// ...
}When using compound namespaces, there MUST NOT be more than two sub-namespaces within the group. That is, the following is allowed:
<?php
use Vendor\Package\SomeNamespace\{
SubnamespaceOne\ClassA,
SubnamespaceOne\ClassB,
SubnamespaceTwo\ClassY,
ClassZ,
};And the following would not be allowed:
<?php
use Vendor\Package\SomeNamespace\{
// This has too many namespace segments to be in a group
SubnamespaceOne\AnotherNamespace\ClassA,
SubnamespaceOne\ClassB,
ClassZ,
};When wishing to declare strict types in files containing markup outside PHP opening and closing tags, the declaration MUST be on the first line of the file and include an opening PHP tag, the strict types declaration and closing tag.
For example:
<?php declare(strict_types=1) ?>
<html>
<body>
<?php
// ...
?>
</body>
</html>Declare statements MUST NOT contain any spaces and MUST be exactly declare(strict_types=1)
(with an optional semicolon terminator).
Block declare statements are allowed and MUST be formatted as below. Note position of braces and spacing:
declare(ticks=1) {
// ...
}The term "class" refers to all classes, interfaces, traits, and enums.
Any closing brace MUST NOT be followed by any comment or statement on the same line.
When instantiating a new class, parentheses MUST always be present even when there are no arguments passed to the constructor. For example:
new Foo();If class contains no additional declarations (such as an exception that exists only to extend another exception with a new type),
then the body of the class SHOULD be abbreviated as {} and placed on the same line as the previous symbol,
separated by a space. For example:
class MyException extends \RuntimeException {}The extends and implements keywords MUST be declared on the same line as
the class name.
The opening brace for the class MUST go on its own line, and MUST NOT be preceded or followed by a blank line.
The closing brace for the class MUST go on its own line, immediately following the last line of the class body, and MUST NOT be preceded by a blank line.
The following is a validly formatted class:
<?php
namespace Vendor\Package;
use FooClass;
use BarClass as Bar;
use OtherVendor\OtherPackage\BazClass;
class ClassName extends ParentClass implements \ArrayAccess, \Countable
{
// ...
}Lists of implements and, in the case of interfaces, extends MAY be split
across multiple lines, where each subsequent line is indented once. When doing
so, the first item in the list MUST be on the next line, and there MUST be only
one interface per line. For example:
<?php
namespace Vendor\Package;
use FooClass;
use BarClass as Bar;
use OtherVendor\OtherPackage\BazClass;
class ClassName extends ParentClass implements
\ArrayAccess,
\Countable,
\Serializable
{
// ...
}The use keyword used inside the classes to implement traits MUST be
declared on the next line after the opening brace.
Each individual trait that is imported into a class MUST be included
one-per-line and each inclusion MUST have its own use import statement.
The following is a correct example of trait usage.
<?php
namespace Vendor\Package;
use Vendor\Package\FirstTrait;
use Vendor\Package\SecondTrait;
use Vendor\Package\ThirdTrait;
class ClassName
{
use FirstTrait;
use SecondTrait;
use ThirdTrait;
}When the class has nothing after the use import statement, the class
closing brace MUST be on the next line after the use import statement.
For example:
<?php
namespace Vendor\Package;
use Vendor\Package\FirstTrait;
class ClassName
{
use FirstTrait;
}Otherwise, it MUST have a blank line after the use import statement, as in:
<?php
namespace Vendor\Package;
use Vendor\Package\FirstTrait;
class ClassName
{
use FirstTrait;
private $property;
}When using the insteadof and as operators they MUST be used as follows taking
note of indentation, spacing, and new lines.
<?php
class Talker
{
use A;
use B {
A::smallTalk insteadof B;
}
use C {
B::bigTalk insteadof C;
C::mediumTalk as FooBar;
}
}Visibility MUST be declared on all properties.
Visibility MUST be declared on all constants.
The var keyword MUST NOT be used to declare a property.
There MUST NOT be more than one property or constant declared per statement.
Property or constant names MUST NOT be prefixed with a single underscore to indicate protected or private visibility. That is, an underscore prefix explicitly has no meaning.
There MUST be a space between type declaration and property name.
A property declaration looks like the following:
<?php
namespace Vendor\Package;
class ClassName
{
public $foo = null;
public static int $bar = 0;
}Visibility MUST be declared on all methods.
Method names MUST NOT be prefixed with a single underscore to indicate protected or private visibility. That is, an underscore prefix explicitly has no meaning.
Method and function names MUST NOT be declared with space after the method name. The opening brace MUST go on its own line, and the closing brace MUST go on the next line following the body. There MUST NOT be a space after the opening parenthesis, and there MUST NOT be a space before the closing parenthesis.
A method declaration looks like the following. Note the placement of parentheses, commas, spaces, and braces:
<?php
namespace Vendor\Package;
class ClassName
{
public function fooBarBaz($arg1, &$arg2, $arg3 = [])
{
// ...
}
}A function declaration looks like the following. Note the placement of parentheses, commas, spaces, and braces:
<?php
function fooBarBaz($arg1, &$arg2, $arg3 = [])
{
// ...
}If a function or method contains no statements or comments (such as an empty no-op implementation or when using
constructor property promotion), then the body SHOULD be abbreviated as {} and placed on the same
line as the previous symbol, separated by a space. For example:
class Point
{
public function __construct(private int $x, private int $y) {}
// ...
}class Point
{
public function __construct(
public readonly int $x,
public readonly int $y,
) {}
}In the argument list, there MUST NOT be a space before each comma, and there MUST be one space after each comma.
Method and function parameters with default values MUST go at the end of the argument list. For example:
<?php
namespace Vendor\Package;
class ClassName
{
public function foo(int $arg1, &$arg2, $arg3 = [])
{
// ...
}
}Argument lists MAY be split across multiple lines, where each subsequent line is indented once. When doing so, the first item in the list MUST be on the next line, and there MUST be only one argument per line.
When the argument list is split across multiple lines, the closing parenthesis and opening brace MUST be placed together on their own line with one space between them. For example:
<?php
namespace Vendor\Package;
class ClassName
{
public function aVeryLongMethodName(
ClassTypeHint $arg1,
&$arg2,
array $arg3 = [],
) {
// ...
}
}When you have a return type declaration present, there MUST be one space after the colon followed by the type declaration. The colon and declaration MUST be on the same line as the argument list closing parenthesis with no spaces between the two characters. For example:
<?php
declare(strict_types=1);
namespace Vendor\Package;
class ReturnTypeVariations
{
public function functionName(int $arg1, $arg2): string
{
return 'foo';
}
public function anotherFunction(
string $foo,
string $bar,
int $baz,
): string {
return 'foo';
}
}In nullable type declarations, there MUST NOT be a space between the question mark and the type. For example:
<?php
declare(strict_types=1);
namespace Vendor\Package;
class ReturnTypeVariations
{
public function functionName(?string $arg1, ?int &$arg2): ?string
{
return 'foo';
}
}When using the reference operator & before an argument, there MUST NOT be
a space after it, like in the previous example.
There MUST NOT be a space between the variadic three dot operator and the argument name:
public function process(string $algorithm, ...$parts)
{
// ...
}When combining both the reference operator and the variadic three dot operator, there MUST NOT be any space between the two of them:
public function process(string $algorithm, &...$parts)
{
// ...
}Classes, properties, and methods have numerous keyword modifiers that alter how the engine and language handles them. When present, they MUST be in the following order:
- Inheritance modifier:
abstractorfinal - Visibility modifier:
public,protected, orprivate - Scope modifier:
static - Mutation modifier:
readonly - Type declaration
- Name
All keywords MUST be on a single line, and MUST be separated by a single space.
The following is a correct example of modifier keyword usage:
<?php
namespace Vendor\Package;
abstract class ClassName
{
protected static string $foo;
private readonly int $beep;
abstract protected function zim();
final public static function bar()
{
// ...
}
}
readonly class ValueObject
{
// ...
}When making a method or function call, there MUST NOT be a space between the method or function name and the opening parenthesis, there MUST NOT be a space after the opening parenthesis, and there MUST NOT be a space before the closing parenthesis. In the argument list, there MUST NOT be a space before each comma, and there MUST be one space after each comma.
The following lines show correct calls:
<?php
bar();
$foo->bar($arg1);
Foo::bar($arg2, $arg3);Argument lists MAY be split across multiple lines, where each subsequent line is indented once. When doing so, the first item in the list MUST be on the next line, and there MUST be only one argument per line. A single argument being split across multiple lines (as might be the case with a closure or array) does not constitute splitting the argument list itself.
The following examples show correct argument usage.
<?php
$foo->bar(
$longArgument,
$longerArgument,
$muchLongerArgument,
);<?php
somefunction($foo, $bar, [
// ...
], $baz);
$app->get('/hello/{name}', function ($name) use ($app) {
return 'Hello ' . $app->escape($name);
});If using named arguments, there MUST NOT be a space between the argument name and colon, and there MUST be a single space between the colon and the argument value. For example:
somefunction($a, b: $b, c: 'c');Method chaining MAY be put on separate lines, where each subsequent line is indented once. When doing so, the first method MUST be on the next line. For example:
$someInstance
->create()
->prepare()
->run();A function or method may be referenced in a way that creates a closure out of it, by providing ... in place of arguments.
If so, the ... MUST NOT include any whitespace before or after. That is, the correct format is foo(...).
The general style rules for control structures are as follows:
- There MUST be one space after the control structure keyword
- There MUST NOT be a space after the opening parenthesis
- There MUST NOT be a space before the closing parenthesis
- There MUST be one space between the closing parenthesis and the opening brace
- The structure body MUST be indented once
- The body MUST be on the next line after the opening brace
- The closing brace MUST be on the next line after the body
The body of each structure MUST be enclosed by braces. This standardizes how the structures look and reduces the likelihood of introducing errors as new lines get added to the body.
An if structure looks like the following. Note the placement of parentheses,
spaces, and braces; and that else and elseif are on the same line as the
closing brace from the earlier body.
<?php
if ($expr1) {
// ...
} elseif ($expr2) {
// ...
} else {
// ...
}The keyword elseif SHOULD be used instead of else if so that all control
keywords look like single words.
Expressions in parentheses MAY be split across multiple lines, where each subsequent line is indented at least once. When doing so, the first condition MUST be on the next line. The closing parenthesis and opening brace MUST be placed together on their own line with one space between them. Boolean operators between conditions MUST always be at the beginning or at the end of the line, not a mix of both.
For example:
<?php
if (
$expr1
&& $expr2
) {
// ...
} elseif (
$expr3
&& $expr4
) {
// ...
}A switch structure looks like the following. Note the placement of
parentheses, spaces, and braces. The case statement MUST be indented once
from switch, and the break keyword (or other terminating keywords) MUST be
indented at the same level as the case body. There MUST be a comment such as
// No break when fall-through is intentional in a non-empty case body.
<?php
switch ($expr) {
case 0:
echo 'First case, with a break';
break;
case 1:
echo 'Second case, which falls through';
// No break
case 2:
case 3:
case 4:
echo 'Third case, return instead of break';
return;
default:
echo 'Default case';
break;
}Expressions in parentheses MAY be split across multiple lines, where each subsequent line is indented at least once. When doing so, the first condition MUST be on the next line. The closing parenthesis and opening brace MUST be placed together on their own line with one space between them. Boolean operators between conditions MUST always be at the beginning or at the end of the line, not a mix of both.
For example:
<?php
switch (
$expr1
&& $expr2
) {
// ...
}Similarly, a match expression looks like the following. Note the placement
of parentheses, spaces, and braces.
<?php
$returnValue = match ($expr) {
0 => 'First case',
1, 2, 3 => multipleCases(),
default => 'Default case',
};A while statement looks like the following. Note the placement of
parentheses, spaces, and braces.
<?php
while ($expr) {
// ...
}Expressions in parentheses MAY be split across multiple lines, where each subsequent line is indented at least once. When doing so, the first condition MUST be on the next line. The closing parenthesis and opening brace MUST be placed together on their own line with one space between them. Boolean operators between conditions MUST always be at the beginning or at the end of the line, not a mix of both.
<?php
while (
$expr1
&& $expr2
) {
// ...
}Similarly, a do while statement looks like the following. Note the placement
of parentheses, spaces, and braces.
<?php
do {
// ...
} while ($expr);Expressions in parentheses MAY be split across multiple lines, where each subsequent line is indented at least once. When doing so, the first condition MUST be on the next line. Boolean operators between conditions MUST always be at the beginning or at the end of the line, not a mix of both. For example:
<?php
do {
// ...
} while (
$expr1
&& $expr2
);A for statement looks like the following. Note the placement of parentheses,
spaces, and braces.
<?php
for ($i = 0; $i < 10; $i++) {
// ...
}Expressions in parentheses MAY be split across multiple lines, where each subsequent line is indented at least once. When doing so, the first expression MUST be on the next line. The closing parenthesis and opening brace MUST be placed together on their own line with one space between them. For example:
<?php
for (
$i = 0;
$i < 10;
$i++
) {
// ...
}A foreach statement looks like the following. Note the placement of
parentheses, spaces, and braces.
<?php
foreach ($iterable as $key => $value) {
// ...
}A try-catch-finally block looks like the following. Note the placement of
parentheses, spaces, and braces.
<?php
try {
// ...
} catch (FirstThrowableType $e) {
// ...
} catch (OtherThrowableType | AnotherThrowableType $e) {
// ...
} finally {
// ...
}Style rules for operators are grouped by arity (the number of operands they take).
When space is permitted around an operator, multiple spaces MAY be used for readability purposes.
All operators not described here are left undefined.
The increment/decrement operators MUST NOT have any space between the operator and operand:
$i++;
++$j;Type casting operators MUST NOT have any space within the parentheses and MUST be separated from the variable they are operating on by exactly one space:
$intValue = (int) $input;All binary arithmetic, comparison, assignment, bitwise, logical, string, and type operators MUST be preceded and followed by at least one space:
if ($a === $b) {
$foo = $bar ?? $a ?? $b;
} elseif ($a > $b) {
$foo = $a + $b * $c;
}The conditional operator, also known simply as the ternary operator, MUST be
preceded and followed by at least one space around both the ?
and : characters:
$variable = $foo ? 'foo' : 'bar';When the middle operand of the conditional operator is omitted, the operator MUST follow the same style rules as other binary comparison operators:
$variable = $foo ?: 'bar';A statement that includes an operator MAY be split across multiple lines, where each subsequent line is indented once. When doing so, the operator MUST be placed at the beginning of the new line; ternaries MUST occupy 3 lines, never 2.
For example:
<?php
$variable1 = $ternaryOperatorExpr
? 'fizz'
: 'buzz';
$variable2 = $possibleNullableExpr
?? 'fallback';
$variable3 = $elvisExpr
?: 'qix';Closures, also known as anonymous functions, MUST be declared with a space
after the function keyword, and a space before and after the use keyword.
The opening brace MUST go on the same line, and the closing brace MUST go on the next line following the body.
There MUST NOT be a space after the opening parenthesis of the argument list or variable list, and there MUST NOT be a space before the closing parenthesis of the argument list or variable list.
In the argument list and variable list, there MUST NOT be a space before each comma, and there MUST be one space after each comma.
Closure arguments with default values MUST go at the end of the argument list.
If a return type is present, it MUST follow the same rules as with normal
functions and methods; if the use keyword is present, the colon MUST follow
the use list closing parentheses with no spaces between the two characters.
A closure declaration looks like the following. Note the placement of parentheses, commas, spaces, and braces:
<?php
$closureWithArgs = function ($arg1, $arg2) {
// ...
};
$closureWithArgsAndVars = function ($arg1, $arg2) use ($var1, $var2) {
// ...
};
$closureWithArgsVarsAndReturn = function ($arg1, $arg2) use ($var1, $var2): bool {
// ...
};Argument lists and variable lists MAY be split across multiple lines, where each subsequent line is indented once. When doing so, the first item in the list MUST be on the next line, and there MUST be only one argument or variable per line.
When the ending list (whether of arguments or variables) is split across multiple lines, the closing parenthesis and opening brace MUST be placed together on their own line with one space between them.
The following are examples of closures with and without argument lists and variable lists split across multiple lines.
<?php
$longArgs_noVars = function (
$longArgument,
$longerArgument,
$muchLongerArgument,
) {
// ...
};
$noArgs_longVars = function () use (
$longVar1,
$longerVar2,
$muchLongerVar3,
) {
// ...
};
$longArgs_longVars = function (
$longArgument,
$longerArgument,
$muchLongerArgument,
) use (
$longVar1,
$longerVar2,
$muchLongerVar3,
) {
// ...
};
$longArgs_shortVars = function (
$longArgument,
$longerArgument,
$muchLongerArgument,
) use ($var1) {
// ...
};
$shortArgs_longVars = function ($arg) use (
$longVar1,
$longerVar2,
$muchLongerVar3,
) {
// ...
};Note that the formatting rules also apply when the closure is used directly in a function or method call as an argument.
<?php
$foo->bar(
$arg1,
function ($arg2) use ($var1) {
// ...
},
$arg3,
);Short closures, also known as arrow functions, MUST follow the same guidelines and principles as long closures above, with the following additions.
The fn keyword MUST NOT be succeeded by a space.
The => symbol MUST be preceded and succeeded by a space.
The semicolon at the end of the expression MUST NOT be preceded by a space.
The expression portion MAY be split to a subsequent line. If so, the => MUST be included
on the second line, and MUST be indented once.
The following examples show proper common usage of short closures.
$func = fn(int $x, int $y): int => $x + $y;
$func = fn(int $x, int $y): int
=> $x + $y;
$func = fn(
int $x,
int $y,
): int
=> $x + $y;
$result = $collection->reduce(fn(int $x, int $y): int => $x + $y, 0);Anonymous Classes MUST follow the same guidelines and principles as closures in the above section.
<?php
$instance = new class {};The opening brace MAY be on the same line as the class keyword so long as
the list of implements interfaces does not wrap. If the list of interfaces
wraps, the brace MUST be placed on the line immediately following the last
interface.
If the anonymous class has no arguments, the () after class MUST be omitted. For example:
<?php
// Brace on the same line
// No arguments
$instance = new class extends \Foo implements \HandleableInterface {
// ...
};
// Brace on the next line
// Constructor arguments
$instance = new class ($a) extends \Foo implements
\ArrayAccess,
\Countable,
\Serializable
{
public function __construct(public int $a)
{
}
// ...
};Enumerations (enums) MUST follow the same guidelines as classes, except where otherwise noted below.
Methods in enums MUST follow the same guidelines as methods in classes. Non-public methods MUST use private
instead of protected, as enums do not support inheritance.
When using a backed enum, there MUST NOT be a space between the enum name and colon, and there MUST be exactly one space between the colon and the backing type. This is consistent with the style for return types.
Enum case declarations MUST use PascalCase capitalization. Enum case declarations MUST be on their own line.
Constants in Enumerations MAY use either PascalCase or UPPER_CASE capitalization. PascalCase is RECOMMENDED, so that it is consistent with case declarations.
The following example shows a typical valid Enum:
enum Suit: string
{
case Hearts = 'H';
case Diamonds = 'D';
case Spades = 'S';
case Clubs = 'C';
public const Wild = self::Spades;
}A nowdoc SHOULD be used wherever possible. Heredoc MAY be used when a nowdoc does not satisfy requirements.
Heredoc and nowdoc syntax is largely governed by PHP requirements with the only allowed variation being indentation. Declared heredocs or nowdocs MUST begin on the same line as the context the declaration is being used in. Subsequent lines in the heredoc or nowdoc MUST be indented once past the scope indentation they are declared in.
The following is not allowed due to the heredoc beginning on a different line than the context it's being declared in:
$notAllowed =
<<<'COUNTEREXAMPLE'
This
is
not
allowed.
COUNTEREXAMPLE;Instead, the heredoc MUST be declared on the same line as the variable declaration it's being set against.
The following is not allowed due to the scope indention not matching the scope the heredoc is declared in:
function notAllowed()
{
$notAllowed = <<<'COUNTEREXAMPLE'
This
is
not
allowed.
COUNTEREXAMPLE;
}Instead, the heredoc MUST be indented once past the indentation of the scope it's declared in.
The following is an example of both heredocs and nowdocs declared in a compliant way:
function allowed()
{
$allowedHeredoc = <<<COMPLIANT
This
is
a
compliant
heredoc
COMPLIANT;
$allowedNowdoc = <<<'COMPLIANT'
This
is
a
compliant
nowdoc
COMPLIANT;
var_dump(
'foo',
<<<'COMPLIANT'
This
is
a
compliant
parameter
COMPLIANT,
'bar',
);
}Arrays MUST be declared using the short array syntax.
<?php
$arr = [];Arrays MUST follow the trailing comma guidelines.
Array declarations MAY be split across multiple lines, where each subsequent line is indented once. When doing so, the first value in the array MUST be on the next line, and there MUST be only one value per line.
When the array declaration is split across multiple lines, the opening bracket MUST be placed on the same line as the equals sign. The closing bracket MUST be placed on the next line after the last value. There MUST NOT be more than one value assignment per line. Value assignments MAY use a single line or multiple lines.
The following example shows correct array usage:
<?php
$arr1 = ['single', 'line', 'declaration'];
$arr2 = [
'multi',
'line',
'declaration',
['values' => 1, 5, 7],
[
'nested',
'array',
],
];Attribute names MUST immediately follow the opening attribute block indicator #[ with no space.
If an attribute has no arguments, the () MUST be omitted.
The closing attribute block indicator ] MUST follow the last character of the attribute name or the closing ) of
its argument list, with no preceding space.
The construct #[...] is referred to as an "attribute block" in this document.
Attributes on classes, methods, functions, constants and properties MUST be placed on their own line, immediately prior to the structure being described.
For attributes on parameters, if the parameter list is presented on a single line, the attribute MUST be placed inline with the parameter it describes, separated by a single space. If the parameter list is split into multiple lines for any reason, the attribute MUST be placed on its own line prior to the parameter, indented the same as the parameter. If the parameter list is split into multiple lines, a blank line MAY be included between one parameter and the attributes of the following parameter in order to aid readability.
If a comment docblock is present on a structure that also includes an attribute, the comment block MUST come first, followed by any attributes, followed by the structure itself. There MUST NOT be any blank lines between the docblock and attributes, or the attributes and the structure.
If two separate attribute blocks are used in a multi-line context, they MUST be on separate lines with no blank lines between them.
If multiple attributes are placed in the same attribute block, they MUST be separated by a comma with a space following but no space preceding. If the attribute list is split into multiple lines for any reason, then the attributes MUST be placed in separate attribute blocks. Those blocks may themselves contain multiple attributes provided this rule is respected.
If an attribute's argument list is split into multiple lines for any reason, then:
- The attribute MUST be the only one in its attribute block.
- The attribute arguments MUST follow the same rules as defined for multiline function calls.
The following is an example of valid attribute usage.
#[Foo]
#[Bar('baz')]
class Demo
{
#[Beep]
private Foo $foo;
public function __construct(
#[Load(context: 'foo', bar: true)]
private readonly FooService $fooService,
#[LoadProxy(context: 'bar')]
private readonly BarService $barService,
) {}
/**
* Sets the foo.
*/
#[Poink('narf'), Narf('poink')]
public function setFoo(#[Beep] Foo $new): void
{
// ...
}
#[Complex(
prop: 'val',
other: 5,
)]
#[Other, Stuff]
#[Here]
public function complicated(
string $a,
#[Decl]
string $b,
#[Complex(
prop: 'val',
other: 5,
)]
string $c,
int $d,
): string {
// ...
}
}