How to tweak glissandos with a scheme function?

[Papa Eric]

Hi, I would like to write a shortcut for glissandos that appear too 
short. Here is what  I have managed to make work so far:

% make next glissando as I want
shortgliss = #(define-music-function (parser location) ()
#{ \once \override Glissando #'thickness = #2
   \once \override Glissando #'gap = #0.1
   \once \override Score.SeparationItem #'padding = #1
#} )

and I use it like:

\shortgliss a8\glissando b8

But I would like to be able to just write:

a8\myglissando b8

or (second best) just: \shortgliss a8 b8

From the manuals I have found no idea of how to write the first, as for 
the second I have tried:

shortgliss = #(define-music-function (parser location m1 m2) (ly:music?
ly:music?)
#{ \once \override Glissando #'thickness = #2
   \once \override Glissando #'gap = #0.1
   \once \override Score.SeparationItem #'padding = #1
   #$m1 \glissando #$m2
#} )

but compilation fails:

<string>:4:16: Erreur : syntax error, unexpected EVENT_IDENTIFIER
   #lilyvartmpe
                \glissando #lilyvartmpf


Is it possible to achieve one of those solutions?

Thanks,
Eric