PHP 8

[i582]

PHP 8.x added a lot of different things and changed a lot of behaviors.
This issue is tracking the status of PHP 8 implementation in KPHP.

The following emoji will be used to denote the task status:

• 🔆 — high priority
• 🔅 — low priority
• 🔸 — breaks backward compatibility
• 🔺 — will not be changed in KPHP
• ⏳ — syntax is supported at the parser level
• 🔨 — in progress

PHP 8.0

Added

New syntax

• Attributes (RFC) 🔆 | initial parser support for attributes #333
• Union types in type hints (RFC) | [compiler] add basic support for type-checked mixed union types #734
• nullsafe operator (?->) (RFC) 🔆 | 🔨 [php8] Nullsafe operator implementation #686
• static return typehint (RFC)
• match expression (RFC) 🔆 | 🔨 match expression #303 Implementation of match expression #724
• throw can be used as an expression (RFC) 🔅
• Block catch without variable (RFC) | allowed catch without variable #309
• Named arguments (RFC) 🔆 | 🔨 WIP: named arguments #317 Named args #853
• Declaring properties in the constructor (RFC) 🔆 | added support for property promotion #310
• Trailing comma in parameter lists and closure use list (RFC), (RFC) | 🔨 allowed trailing comma for function parameter lists and closure use lists #308 Allow trailing comma for function use and parameter lists #664

Other

• Stringable interface (RFC) 🔅
• Ensure correct signatures of magic methods (RFC)
• Add str_starts_with and str_ends_with (RFC) 🔅
• Add str_contains (RFC) 🔅

Changed

• Saner numeric strings (RFC) 🔸
• Saner string to number comparisons (RFC) 🔸
• Locale-independent float to string cast (RFC) 🔸
• Sorting now stable (RFC) 🔸
• Names in the namespace are treated as a single token (RFC)
• Deferencable changes and arbitrary expressions in new/instanceof (RFC)
• Access ::class on object (RFC) 🔅
• Concatenation precedence (RFC) 🔸
• Arrays starting with a negative index (RFC) 🔸

Removed

• Remove (real) cast (without separate RFC) 🔺

• Remove (unset) cast (without separate RFC) 🔺

• Remove {} access (without separate RFC) 🔺

PHP 8.1

Added

New syntax

• Readonly properties (RFC) | added readonly modifier support for properties #307
• never type (RFC) | added support for never type #337
• Enums (RFC) 🔆 | 🔨 Implementation of enum #824
• Final class constants (RFC) | added support for final constants #336
• ⏳ First-class callable syntax (RFC) 🔨
• ⏳ Explicit octal integer literal notation (RFC) 🔅 🔨
• Pure intersection types (RFC) 🔺

Other

• array_is_list(array $array): bool (RFC)

Changed

• New in initializers (RFC)
• Array unpacking with string keys (RFC) 🔸
• Static variables in inherited methods (RFC) 🔺

PHP 8.2

Added

New syntax

• ⏳ Readonly classes (RFC) 🔨
• ⏳ Disjunctive Normal Form Types (RFC) 🔨
• Allow null and false as stand-alone types (RFC) | commit
• ⏳ Add true type (RFC) 🔨
• ⏳ Constants in Trait (RFC) 🔨

Other

• Add flag FILTER_FLAG_GLOBAL_RANGE

Changed

• Deprecate dynamic properties (RFC)
• Deprecate ${} string interpolation (RFC)
• DateTime::createFrom(Im|M)utable return type changed from DateTime to static
• strtolower(), strtoupper(), stristr(), stripos(), strripos(), lcfirst(), ucfirst(), ucwords(), and str_ireplace() are no longer locale-sensitive
• str_split() returns an empty array for an empty string now
• Callables that are not accepted by the $callable() syntax (but are accepted by call_user_func()) are deprecated:
  • self::method
  • parent::method
  • "static::method"
  • ["self", "method"]
  • ["parent", "method"]
  • ["static", "method"]
  • ["Foo", "Bar::method"]
  • [new Foo, "Bar::method"]