Error Identifier: argument.templateType

← Back to argument.*

Every error reported by PHPStan has an error identifier. Here’s a list of all error identifiers. In PHPStan Pro you can see the error identifier next to each error and filter errors by their identifiers.

Code example #

<?php declare(strict_types = 1);

/**
 * @template T of int
 * @param T $value
 * @return T
 */
function identity($value)
{
	return $value;
}

$result = identity('hello');

Why is it reported? #

The called function or method declares a template type (generic type parameter) with a bound, but the provided argument does not satisfy the bound. PHPStan cannot resolve the template type because the argument type falls outside the allowed range specified by the @template T of ... constraint.

In the example above, the template type T is bounded to int, but a string is passed. PHPStan cannot resolve T because string is not a subtype of int.

Learn more: Solving PHPStan error “Unable to resolve template type”

How to fix it #

Pass an argument that satisfies the template bound:

 <?php declare(strict_types = 1);
 
-$result = identity('hello');
+$result = identity(42);

Or widen the template bound if more types should be accepted:

 <?php declare(strict_types = 1);
 
 /**
- * @template T of int
+ * @template T of int|string
  * @param T $value
  * @return T
  */
 function identity($value)
 {
 	return $value;
 }

How to ignore this error #

You can use the identifier argument.templateType to ignore this error using a comment:

// @phpstan-ignore argument.templateType
codeThatProducesTheError();

You can also use only the identifier key to ignore all errors of the same type in your configuration file in the ignoreErrors parameter:

parameters:
	ignoreErrors:
		-
			identifier: argument.templateType

Rules that report this error #

PHPStan\Rules\Classes\ClassAttributesRule [1]
PHPStan\Rules\Classes\ClassConstantAttributesRule [1]
PHPStan\Rules\Classes\InstantiationRule [1]
PHPStan\Rules\Constants\ConstantAttributesRule [1]
PHPStan\Rules\EnumCases\EnumCaseAttributesRule [1]
PHPStan\Rules\Functions\ArrowFunctionAttributesRule [1]
PHPStan\Rules\Functions\CallCallablesRule [1]
PHPStan\Rules\Functions\CallToFunctionParametersRule [1]
PHPStan\Rules\Functions\CallUserFuncRule [1]
PHPStan\Rules\Functions\ClosureAttributesRule [1]
PHPStan\Rules\Functions\FunctionAttributesRule [1]
PHPStan\Rules\Functions\ParamAttributesRule [1]
PHPStan\Rules\Methods\CallMethodsRule [1]
PHPStan\Rules\Methods\CallStaticMethodsRule [1]
PHPStan\Rules\Methods\MethodAttributesRule [1]
PHPStan\Rules\Properties\PropertyAttributesRule [1]
PHPStan\Rules\Properties\PropertyHookAttributesRule [1]
PHPStan\Rules\Traits\TraitAttributesRule [1]

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