Re: Cleaning up code

[Stefan Monnier <monnier@iro.umontreal.ca>]

> There is also another case where it doesn't work as expected. Often, I
> let bind a variable for side effect, like this:

>       (let ((default-directory (tramp-compat-temporary-file-directory))
>             (outline-regexp tramp-debug-outline-regexp))
>         (outline-mode))

> And I get from the byte compiler

> tramp.el:1400:1:Warning: Unused lexical variable `outline-regexp'

That is a correct warning, telling you that it treated outline-regexp as
a lexical variable and hence that it did not generate the code you want.
IOW you need to add

   (defvar outline-regexp)


-- Stefan