docs: add usage to config reference

[brunetton]

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Other information:

[billyyyyy3320]

There's configuration section in guide already, and it's precise enough IMO.

[brunetton]

You HO is the opinion of a developer of the project, using it for years probably. In your position, everything is obvious.
If I took time to make this PR, it's because for a new user (2 on this case), this is far from being obvious. IMHO newcomers remarks are super precious when I start a project (except for personal project that I absolutely don't document at all).
Maybe you want all new users to use another project, more documented, and this project to be forgot by the community ?
In our company, we stopped trying to use VuePress and swapped to another technology already. But we wanted to take time to help you identify when new users loose time.

So, if you don't want to repeat yourself in doc (which is a good thing), why don't you add a link to the doc section you pointed out with something like "for more details it's here"? Does it prevents advanced users from read the doc anyway? I doubt advanced users read this section of the doc so this is clearly for newcomers.

[billyyyyy3320]

@brunetton That's why I left it open so that I can get your feedback which I didn't see in this PR. I assumed that new users should have read the guide section first. Apologies if my words offended you.

Agreed with your point about adding a reference link.

Here's my suggestion:

1. Maybe using a code block to demonstrate will be more precise, such as:

module.exports = {
  // ...config
}

2. Add it before Basic Config since not only basic config are going to be place in .vuepress/config.js

[brunetton]

No offense here, don't worry! Just arguing because I had some time.
Yes a little code block or a reference is perfect (or both). I don't think this need to spend time to choose the perfect form, the important thing is that information is there (IMHO, of course).
Thank for replying, have a nice day