Hello internals,
I'm ready as I'm going to be to introduce to you: "Records"
https://wiki.php.net/rfc/records!
Records allow for a lightweight syntax for defining value objects. These are
superior to read-only classes due to having value semantics and far less
boilerplate, for most things developers use read-only classes for. They are
almost as simple to use as arrays (and provide much of the same semantics), but
typed.
As an example, if you wanted to define a simple User record:
record User(string $emailAddress, int $databaseId);
Then using it is as simple as calling it like a function, with the & symbol:
$rob = &User("rob@bottled.codes", 1);
Since it has value semantics, we can get another instance, and it is strongly
equal to another of the same parameters:
$otherRob = &User("rob@bottled.codes", 1);
assert($otherRob === $rob); // true
Records may also have methods (even hooks), use traits, and implement
interfaces:
record Vector3(float $x, float $y, $z) implements Vector {
use Vector;
public float magnitude {
get => return sqrt($this->x ** 2 + $this->y ** 2 + $this->z ** 2)
}
}
Further, an automatic (but overridable) "with" method is generated for every
record. This allows you to get a new record similar to a given one, very easily:
record Planet(string $name);
$earth = &Planet("earth");
$mars = $earth->with(name: "mars");
The depth of records was an immense exploration of the PHP engine, language
design, and is hopefully quite powerful for the needs of everyday PHP and niche
libraries. I took care in every aspect and tried to cover every possible case
in the RFC, but I still probably missed some things. I plan on having a full
implementation done by the end of the year and open to a vote by the end of
January, but I'd like to open the discussion up here first. Love it or hate it,
I'd like to hear your thoughts.
— Rob
