Plugins system for Delphi application - bpl vs dll?

Question

I'm writing delphi app which should have capability of loading plugins. I'm using JvPluginManager as plugin system/manager ;) Now, in the new plugin wizard they say it's better to use .bpl type plugins instead of .dll plugins ... What are the pros of this solution versus dll type plugins? So far I've found only cons of this solution:

1. I have to put all the common interface units in separate package so that while loading plugins it won't throw any error about the other package containing common unit

2. if, let's say, one of plugin developers decides to uses some well-known unit (like synapse), which doesn't have runtime package by default, and the second plugin developer does the same, than bump... it's crash here ...

So, what are actually the pros of using bpls instead of dlls compiled with runtime packages?

Thanks in advance

Answer 1

Another disadvantage to BPL's. When you switch Delphi versions you will have to re-distribute new plugins. After many attempts at attempting to find the perfect plugin system, I ended up with COM and I have never regretted that decision. In a commercial application which has had the plugin requirement for over 8 years, the application has continued to move forward and yet some of the plugins that were released with the first iteration still exist in their ORIGINAL form.

If you choose this method, do yourself a favor and start with a simple interface and then add new interfaces upon it. You don't want to ever change your base interface, so keep it simple and sweet.