@ Frank: Thank you for your suggestion, Frank, but your definition does not work, if you try to evaluate lf[{Cos, Sin}] [0].
@ Michael: It is very similar to the Function through. The only difference I'm aiming at is to uncouple it from the variable.
lf2 = Function[{a, b, c, d}, Function[x, Through[{a, b, c, d}[x]]]]
Here again I have the problem that the definition works only for a fixed number of function.
»Through« has the disatvantage, that it can't be used inside a »Composition«, while »lf« works: e.g.:
Composition[f, lf2[a, b, c, d], h][x]
for suitable »f« and »h«.
But the problem remains to generalizing the definition to arbitrary many functions.
