psalm/docs/running_psalm/issues/TooManyTemplateParams.md

TooManyTemplateParams

Emitted when using the @extends/@implements annotation to extend a class and adds too many types.

<?php

/**
 * @template-implements IteratorAggregate<int, string, int>
 */
class SomeIterator implements IteratorAggregate
{
    public function getIterator() {
        yield 5;
    }
}