auto-save-file-name-transforms: When is it applied?

[XeCycle]

Hello,

I don't like the default auto-save file name, since it doesn't
start with a period `.'.  So I modified this variable:

(add-to-list 'auto-save-file-name-transforms
             '("\\`\\(.*\\)/\\([^/]*\\)\\'" "\\1/.\\2" nil))

However, for a file like ~/sdf, the auto save file name became
~/#.sdf#.  Seems the transform is done before prepending and
appending #.  I remember some time ago, with some other
customization, the name can be like .#sdf#, but I lost that
configuration.  How can I change that?

Thank you.

-- 
Carl Lei (XeCycle)
Department of Physics, Shanghai Jiao Tong University
OpenPGP public key: 7795E591
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