Adding return types to existing implementations will still be compatible with psr/container 1.0 also because of PHP's covariance rules, while adding compatibility with psr/container 2.0. Leaving off parameter types similarly will maintain compatibility with both as per PHP's contravariance rules.
Adding return types to existing implementations will still be compatible with psr/container 1.0 also because of PHP's covariance rules, while adding compatibility with psr/container 2.0. Leaving off parameter types similarly will maintain compatibility with both as per PHP's contravariance rules.