how to set vimrc tags to use shell environment variables

Question

I tried but failed and need an expert help. In a .vimrc I have the following: `set tags=/sandbox/myNameIsSam/tags` This works just fine. Inside gvim, I can load the tags file and everything is awesome. However, I would like for each user to have their own project tags file. How and why is not important here. The below setting doesn't seem to do what I need. Can someone help? ``` let projectTagFile='/sandbox/'.$USERNAME.'/tags' set tags=projectTagFile ```

Accepted Answer

you should get username by `$USER` not `$USERNAME`

What is important is that in this particular case, you cannot use `set` to set this option because it only allows you to set it to a single literal value. However, with `let`, you can use Vimscript to obtain the value using a function, for example, or in your case, through concatenation (read more about about options here). Try this instead:

```
let &tags='/sandbox/'.$USER.'/tags'
```

To check if the `tags` was set correctly, you could execute:

```
:set tags?
```

Or, for the fully-qualified path:

```
:echo &tags
```

how to set vimrc tags to use shell environment variables

Solution

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