Dub Error Message "Invalid variable: DUB"

[Andre Pany]

On Sunday, 7 June 2020 at 16:54:48 UTC, Paul Backus wrote:
> On Sunday, 7 June 2020 at 16:26:17 UTC, Andre Pany wrote:
>> On Sunday, 7 June 2020 at 15:37:27 UTC, Paul Backus wrote:
>>> On Sunday, 7 June 2020 at 12:52:12 UTC, Andre Pany wrote:
>>>>
>>>> I am not sure but $DUB is a variable which could be used in 
>>>> dub descriptor file but it isn't an environment variable.
>>>>
>>>> $DUB_EXE is an environment variable.
>>>>
>>>> Kind regards
>>>> Andre
>>>
>>> If what you say is true, the Dub documentation needs to be 
>>> updated:
>>>
>>> https://dub.pm/package-format-json.html#environment-variables
>>
>> Each of the table has an explanation section were they can be 
>> used. $DUB can only be used within the dub descriptor but not 
>> within scripts called from the hooks.
>>
>> From the hooks you can use these environment variables: 
>> https://github.com/andre2007/dub/blob/376ff5854dcd7bbc6116f72001c8c6d13eb3cbf0/source/dub/generators/generator.d#L763
>>
>> Kind regards
>> Andre
>
> The documentations says:
>
>> Inside of custom commands directives a number of additional 
>> variables is available:
>
> ...and then lists the variables from the function you linked 
> to. "Additional" implies that they are not the only variables 
> that can be used in hooks, and that the variables listed 
> previously (such as $DUB) can also be used. If this is not the 
> case, then the documentation is inaccurate and should be 
> updated.
>
> I would also add: if you feel the need to link to the source 
> code to explain to use a feature, rather than referring to the 
> documentation, that is a good sign that the documentation is 
> inadequate.

I had a second look on the descriptions and from a non native 
speaker view it sounds correct.
But you are right from a native speaker view the wording might be 
incorrect.

If you have time, could you check the wording and make a proposal?

https://github.com/dlang/dub-docs/blob/master/views/inc.package_format.envvars.dt

Kind regards
Andre