System operating detection

[Andrea Crotti]

Is there a way to make this ugly thing:

--8<---------------cut here---------------start------------->8---
  (defconst sysop
    (cond
     ((string-match "linux" system-configuration) "linux")
     ((string-match "apple" system-configuration) "mac")
     ((string-match "win" system-configuration) "win")
     (t "other")))
  
  (defconst linux (string= "linux" sysop))
  (defconst mac (string= "mac" sysop))
  (defconst win (string= "win" sysop))
  (defconst other (string= "other" sysop))
--8<---------------cut here---------------end--------------->8---

looking better?
I would like to have all the constants defined (to nil or t) but
avoiding this ugly repetition.
One (small) problem is that without the "cond" also "darwin" matches
"win", so I get a wrong constant...