ELI5: ClojureScript uses an advanced Google Javascript compiler that eliminates dead code. To make that possible you have to be super careful about how you refe

ELI5: ClojureScript uses an advanced Google Javascript compiler that eliminates dead code. To make that possible you have to be super careful about how you reference external javascript libraries in your code, because these will get sucked into the dead code elimination- Which is GOOD, because you want to remove all the unused gunk from your libraries, but it's also BAD because only advanced ClojureScript users could sometimes figure out how to reference a new library. This "externs inference" feature is the first step into automating the importing of javascript libraries, in order to make the process easier.