Bad license when operator '+' is used

[FedericoVaga]

The command reuse lint reports the use of a BAD license when the '+' operator is used.

https://spdx.github.io/spdx-spec/appendix-IV-SPDX-license-expressions/#simple-license-expressions

From this page I understand that the '+' operator can be applied on any license in https://spdx.org/licenses/ (except the already marked -or-later). But despite this if I use it I get:

* Bad licenses: CERN-OHL-W-2.0+

[mxmehl]

True, + seems to be a valid SPDX expression. I wonder why we didn't support this from the start.

@silverhook, just for the sake of completeness: can you confirm that REUSE should support + expression except for the explicitely marked licenses which are supposed to use -or-later?

[silverhook]

I confirm that + is a valid SPDX expression, which according to the spec can be applied to any license ID.

The fact that the GPL family of licenses use the -or-later (and -only) suffixes, is an exception to the above, and is a result of a request of and subsequent long discussion with the FSF. If you are interested, here is an incomplete summary into that. Prior to this change, you would also indicate GPL-2.0+ instead of GPL-2.0-or-later – the former is still valid ID if you rely on an older SPDX Spec/Licese List.

The reuse tool should acknowledge the use of the +, yes.

[mxmehl]

Thanks for the confirmation, Matija!

[carmenbianca]

#314 should fix this.

[brlin-tw]

Consider making a release that contains the patch of this issue as + license is quite common.