Syntax Comparison

Edit pageLast modified: 10 January 2025

The language is defined by a syntax that is based on the grammar of popular static code analysis tools: PHPStan and Psalm.

tip

There are others that are not currently tested for compatibility. For example:

If you wish, you can add information about this software using a pull request to the documentation.

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Below is a comparison list of all syntactic structures (grammar). The logical component (the physical existence of the type) is NOT taken into account.

General table across all type parsing capabilities

  TypeLang

  Psalm

  PHPStan

note

62/62

warning

42/62

warning

46/62

Basic Types

Below is a list of simple, logical and other common types.

  TypeLang

  Psalm

  PHPStan

note

11/12

warning

9/12

warning

10/12

Class or type name (including FQN)

Fully\Qualified\Name

Logical union types

T | U | V

Logical intersection types

T & U & V

Logical nullable types

?T

Legacy list types syntax

User[]

Template arguments (Generics)

ExampleCollection<array-key, User>

Trailing comma not supported 1

Template argument hints

ExampleCollection<in array-key, out User>

Not Supported

Call-site variance 1

Template argument attributes

ExampleCollection<#[assert(not<"0">)] array-key>

Not Supported

Not Supported

Class constant types

ClassName::CONSTANT_NAME

Prefixed class constant mask types

ClassName::CONSTANT_*

Non-prefixed class constant mask types

ClassName::*

Global constant mask types

JSON_*

Not Supported

Not Supported

Conditional Types

Below is a list of conditional types.

  TypeLang

  Psalm

  PHPStan

note

6/6

warning

4/6

warning

4/6

Conditional positive equality types

T is A ? B : C

Conditional negative equality types

T is not A ? B : C

Conditional referenced types

$var is A ? B : C
$var is not A ? B : C

Conditional referenced types in Yoda-style

A is $var ? B : C
A is not $var ? B : C

Not Supported

Not Supported

Functions in conditional types

foo() is A ? B : C
foo() is not A ? B : C

List of supported functions 1

List of supported functions 2

Functions in conditional types in Yoda-style

A is foo() ? B : C
A is not foo() ? B : C

Not Supported

Not Supported

Literal Types

Below is a list of literal types/lexemes.

  TypeLang

  Psalm

  PHPStan

note

19/19

warning

7/19

warning

11/19

Boolean true and false literals

true
false

The null literals

null

Single-quoted string literals

'single-quoted string'

Double-quoted string literals

"double-quoted string"

Escape sequences in a double-quoted string literals

"string with \n new line \n delimiters"

Not Supported

Not Supported

Hexadecimal sequences in a double-quoted string literals

"\xDE\xAD\xBE\xEF"

Not Supported

Not Supported

Unicode sequences in a double-quoted string literals

"This is smile \u{1F60A}"

Not Supported

Not Supported

Integer literals

42

BigInteger (PHP_INT_MAX + 1 or PHP_INT_MIN - 1) literals

42

Works with restrictions 1

Works with restrictions 2

Works with restrictions 3

Integer literals in binary format

0b10101010

Not Supported

Not Supported

Integer literals in octal format

0o42

Not Supported

Not Supported

Integer literals in legacy octal format

042

Not Supported

Not Supported

Integer literals in hexadecimal format

0xDEAD_BEEF

Not Supported

Not Supported

Float literals

0.42

Float literals without leading zero

.42

Not Supported

Float literals without trailing zero

42.

Not Supported

Float literals in scientific notation

2e2

Not Supported

Float literals in scientific notation

2e2

Not Supported

Float hexadecimal literals in scientific notation

0x42e2

Not Supported

Not Supported

Shape Types

Below is a list of grammar of shaped types.

  TypeLang

  Psalm

  PHPStan

note

11/11

warning

9/11

warning

10/11

Explicit shape types

object {
    key: ValueType
}

Works with restrictions 1

Trailing comma in explicit shape types

object {
    key: ValueType,
}

Works with restrictions 1

Implicit shape types

object {
    ValueType
}

Works with restrictions 1

Trailing comma in implicit shape types

object {
    ValueType,
}

Not Supported

Optional keys in explicit shape types

object {
    key?: ValueType
}

Works with restrictions 1

Empty (closed) shape types

object {}

Works with restrictions 1

Unsealed shape types

object { ... }

Works with restrictions 1

Explicit unsealed shape types

object {
    key: ValueType,
    ...
}

Works with restrictions 1

Implicit unsealed shape types

object {
    ValueType,
    ...
}

Works with restrictions 1

Typed unsealed shape types

object {
    ...<array-key, Type>
}

Works with restrictions 1

Works with restrictions 2

Shape field attributes

object {
    #[inline, assert(not<"">)]
    name: string
}

Callables Types

Below is a list of grammar of callable (function) types.

  TypeLang

  Psalm

  PHPStan

note

15/15

warning

13/15

warning

12/15

Non-typed callable types

callable()

Not Supported

Typed callable types

callable(): Type

Callable with typed parameters

callable(Type): T

Callable with optional parameters

callable(Type=): T

Callable with named parameters

callable(Type $name): T

Callable with optional named parameters

callable(Type $name=): T

Not Supported

Callable with output parameters

callable(T&): T

Works with restrictions 1

Callable with output optional parameters

callable(T&=): T

Works with restrictions 1

Callable with output optional named parameters

callable(T &$name=): T

Not Supported

Callable with suffixed variadic parameters

callable(Type...): T

Callable with prefixed variadic parameters

callable(...Type): T

Not Supported

Callable with prefixed and suffixed variadic parameters

callable(...Type ...$name): T

Works with restrictions 1

Works with restrictions 2

tip

This expression is incorrect because the "variadic" lexeme ... must be present in the parameter in a single copy. The parser must throw a syntax or semantic error.

Callable with optional variadic parameters

callable(Type...=): T
callable(...Type=): T

Works with restrictions 1

No Error

tip

This expression is incorrect because any variadic parameter is already optional. The parser must throw a syntax or semantic error.

Callable with named variadic parameters

callable(Type ...$name): T
callable(...Type $name): T

Works with restrictions 1

Works with restrictions 2

Callable with output named variadic parameters

callable(Type &...$name): T
callable(...Type &$name): T

Works with restrictions 1

Works with restrictions 2