evaluate regular expressions

[sol1105]

There is a typo in the CV attribute driving_variant_label. It is currently called driving_variant_labelin the required_global_attributes, but missing the driving_ prefix in the actual CV entry (so just being called variant_label).

:1438        "variant_label": [
:1439            "r[[:digit:]]\\{1,\\}i[[:digit:]]\\{1,\\}p[[:digit:]]\\{1,\\}f[[:digit:]]\\{1,\\}$"

[sol1105]

version_realization does not have an entry, it could have an entry similar to driving_variant_label.

        "version_realization": [
            "v[[:digit:]]\\{1,\\}-r[[:digit:]]\\{1,\\}$"

Since 0 is not allowed(?!), maybe this example would have to be modified, eg.

 "version_realization": [
            "v[1-9]\\{1,\\}[[:digit:]]\\{0,\\}-r[1-9]\\{1,\\}[[:digit:]]\\{0,\\}$"

[larsbuntemeyer]

Thanks for pointin this out. That's another relict from the original CMIP6 CV. We did not really change the convention on the variant label so keepin the original regex should be fine. However, i could not really figure out how to evaluate these regex, e.g., have the same questions as in PCMDI/cmip6-cmor-tables#281. Do you know, if cmor actually evaluates regex during cmorization?

[larsbuntemeyer]

My closest approach to evaluate regex is this:
https://github.com/euro-cordex/cmor-check/blob/2eb19b36bf39cc1dd1f1a6c93b993a37a1b27331/cmor_check/cmor_check.py#L11-L14

However, that won't work for most of the regular expressions, e.g., in the CMIP6_CV.

[sol1105]

The problem seems to be that the re module in python doesn't know [[:digit:]]. It also seems to not like all the backslashes. Without those, and with [[:digit:]] replaced by \d it works.