--- layout: default title: Upgrading from 2.3 to 2.4 description: Guide to upgrading to newer versions of this library --- # Upgrading from 2.3 to 2.4 ## Exception Changes Prior to 2.4.0, this library did a poor job of using appropriate exception types and documenting which exceptions could be thrown. For example, all of the main interfaces said that only `RuntimeException` could be thrown, but in reality other exceptions like `LogicException` or `InvalidArgumentException` could be thrown in some cases! This inconsistent behavior and inaccurate documentation has been fixed in 2.4.0 by: - Adding a new `CommonMarkException` interface implemented by all exceptions thrown by this library - Adding several new exception types that implement that interface while also extending from the same base exception type as that would have been previously thrown. - Fixing incorrect docblocks about the exception types being thrown If you were previously catching exceptions thrown by this library in your code, you should consider changing your `catch` blocks to either catch `CommonMarkException` (for all exceptions) or one of the exception types under the `League\CommonMark\Exception` namespace.