The override option introduced in #87 by @jfairley conflicts with the cascade option when both are used together.

Example

.env

MY_NAME=Bob

.env.local

MY_NAME=Joe

Command

> dotenv -c -- bash -c 'echo $MY_NAME'
Joe
> dotenv -co -- bash -c 'echo $MY_NAME'
Bob

I would expect Joe from .env.local to override Bob from .env based on how cascade works, but when the override option is present Bob prevails because .env is processed last (see here and here).