@param-outassignString($value), analyzers that honor @param-out string
narrow $value to string so a later takesString($value) is valid.
Tools that ignore the annotation keep the pre-call type (null) and
report an argument error — or accept via mixed looseness.
References:
- Psalm assertion / param-out annotations
- PHPStan param-out support| Analyzer | Version | Result | Diagnostics |
|---|---|---|---|
| phan | 6.0.7Phan 6.0.7 php-ast version 1.1.3 PHP version used to run Phan: 8.5.9 | Enforced | No diagnostics reported.
|
| phpstan | 2.2.8PHPStan - PHP Static Analysis Tool 2.2.8 | Enforced | No diagnostics reported.
|
| psalm | 6.16.1Psalm 6.16.1@f1f5de594dc76faf8784e02d3dc4716c91c6f6ac next: 7.0.0-beta19 |
Enforced | No diagnostics reported.
|
| mago | 1.46.0mago 1.46.0 | Enforced | No diagnostics reported.
|
| mir | 0.70.1mir 0.70.1 | Enforced | No diagnostics reported.
|
| phpantom | 0.9.0phpantom_lsp 0.9.0 | Not enforced | assertions_param_out.php:42: Argument 1 ($value) expects string, got null [type_mismatch_argument]
|
| intelephense | 1.18.5intelephense 1.18.5 | Enforced | No diagnostics reported.
|
| phpy | 0.2.0phpy 0.2.0 | Enforced | No diagnostics reported.
|
| qodana | 262.8665.325Qodana 262.8665.325 | Not enforced | assertions_param_out.php:42: Parameter '$value' type is not compatible with declaration [PhpStrictTypeCheckingInspection]
|
| noverify | 0.5.5NoVerify, version 0.5.5: built on: 2025.04.22 14:36:46 OS: r-kuchinskas arm64 Commit: 4774b82f8adc53fbef38f95e97af4b953b4d1529 | Not enforced | assertions_param_out.php:42: not null safety call in function Conformance\Tests\AssertionsParamOut\takesString signature of param value [notNullSafetyFunctionArgumentVariable]
|
| steins | 0.1.5steins 0.1.5 (2026-08-12 revision 39b4cc1) | Enforced | No diagnostics reported.
|
| phpstan-strict | 2.2.8PHPStan - PHP Static Analysis Tool 2.2.8 | Enforced | No diagnostics reported.
|
| psalm-next | 7.0.0-beta19Psalm 7.0.0-beta19@7e751c06a756fa64dc4c759c09fe4a173afcb433 | Enforced | No diagnostics reported.
|
<?php
declare(strict_types=1);
namespace Conformance\Tests\AssertionsParamOut;
/**
* By-reference output parameters via `@param-out`.
*
* After `assignString($value)`, analyzers that honor `@param-out string`
* narrow `$value` to string so a later `takesString($value)` is valid.
* Tools that ignore the annotation keep the pre-call type (`null`) and
* report an argument error — or accept via mixed looseness.
*
* References:
* - Psalm assertion / param-out annotations
* - PHPStan param-out support
*/
/**
* @param-out string $value
* @psalm-param-out string $value
* @phpstan-param-out string $value
*/
function assignString(?string &$value): void // T: @param-out
{
$value = 'assigned';
}
function takesString(string $value): void
{
}
function example(): void
{
$value = null;
assignString($value);
// After @param-out string, $value is string, so this must be silent.
// A diagnostic here means the tag was ignored (or the tool never flags
// null for string). Silence is the honour signal, not a report.
takesString($value); // Q?: after @param-out string, $value is string
}