PHP ya kisasa inasaidia type declarations kwenye function parameters, return values, na class properties — na declare(strict_types=1) kuzilazimisha kwa ukali. Kwa pamoja huleta usalama mwingi wa statically-typed languages kwa PHP, ikinasa bugs mapema.
{
= ;
? = ;
{
->balance += ;
}
{
->balance;
}
}
Unaweza ku-type parameters, return values, na class properties. Types zinajumuisha scalars (int, float, string, bool), classes/interfaces, array, ?Type (nullable), na void.
function process(int|string $id): User|null { } // union type — int OR string
function handle(Countable&Iterator $x): void { } // intersection (PHP 8.1) — BOTH
function get(): static { } // return the called class's type
function nothing(): never { } // never returns (throws/exits, PHP 8.1)
PHP 8 iliongeza union types (int|string), intersection types, na special return types (static, never).
<?php
declare(strict_types=1); // MUST be the first statement in the file
function add(int $a, int $b): int { return $a + $b; }
add(5, 3); // ✅ 8
add("5", 3); // ❌ TypeError — strict_types REJECTS the string (no coercion)
WITHOUT strict_types (default "coercive" mode):
add("5", 3) → "5" is silently coerced to int 5 → returns 8 (lenient, can hide bugs)
WITH strict_types=1:
add("5", 3) → TypeError immediately (must pass the exact declared type)
declare(strict_types=1) hubadilisha kutoka lenient coercion hadi strict enforcement — PHP hukataa type mismatches badala ya kuzigeuza kimyakimya. Hii hunasa bugs ambazo coercion ingeficha.
Type declarations na strict types ni muhimu kwa kuandika PHP ya kisasa imara, inayoweza kudumishwa, na zinawakilisha mageuzi makubwa ya lugha zaidi ya asili yake ya loosely-typed.
Type declarations kwenye parameters, returns, na properties huzifanya code kujieleza yenyewe (signatures huonyesha matarajio wazi) na huruhusu PHP kunasa type errors kiotomatiki, wakati nyongeza za kisasa (union types, nullable types) huzifanya signatures kuwa sahihi.
Mazoea muhimu zaidi ni declare(strict_types=1): hubadilisha PHP kutoka lenient coercion (ambapo "5" hubadilika kimyakimya kuwa 5, ikiwezekana kuficha bugs) hadi strict enforcement (kukataa types zisizolingana kwa TypeError wazi) — chombo muhimu cha kunasa bugs mapema na kuandika code ya kuaminika, na chaguo-msingi cha kisasa kinachopendekezwa.
Kuelewa type declarations na kutumia strict types ni ujuzi wa kitaalamu wa kila siku kwa maendeleo ya PHP ya kisasa — huleta usalama mwingi wa statically-typed languages kwa PHP, ukifanya code kuwa imara zaidi na rahisi kudumisha.
Kwa kuwa frameworks za PHP za kisasa na codebases zilizoandikwa vizuri hutumia typing kwa wingi (na strict types kote), kumudu hii ni muhimu kwa kuandika na kufanya kazi na PHP bora ya sasa, ukitofautisha code ya kisasa salama kitype na mtindo wa loosely-typed wenye makosa wa PHP ya zamani.