@nomasprime No problem, appreciate the response!

As noted on #170, the issue of dealing with unknown flags is not a straightforward resolution. I'm open to discuss options to improve this situation.

Taking far too long to figure out how to use this from the readme. A practical real world example would be really helpful.

The readme includes a few examples. I believe the main example at the top is "real world", but again if you have ideas for improving this I'd love to hear them.

I think we should fix this but we should also enable frozen strings in Slop using the # frozen_string_literal: true pragma

Ah I've just read the issue. You must be running with frozen string literals. I'm up for fixing this but I'm still interested in how/why you received this error message. Do you have # frozen_string_literal: true at the top of your Ruby files or something else?

Moving discussion to that PR

I just ran into a problem in the to_s method of Slop::Options. The lines where where << is used on the local variable 'str' are raising the error ...

/Users/dewayne/.rvm/gems/ruby-2.7.1/gems/slop-4.8.2/lib/slop/options.rb:108:in `block in to_s': can't modify frozen String: "Install stuff from the directory common_debug into the current project\n" (FrozenError)

Looks like replacing the "str <<" with "str +=" fixes it. I will work up a PR.

What version of Ruby are you using, @MadBomber? We have specs that run against all of these versions and they're currently all passing, so if there's a version the tests are failing on I'd want to add that to the matrix.