problems with integration

[Snorre]

(01-10-2015 03:17 PM)parisse Wrote:  [...] You can not use g like if it was a function, g(2) is invalid, [...]

Numbers seem to be treated like constant functions: If "g:=2" then "g", "g(x)", "g(x,y,z)" evaluate to "2".
Your explanation makes me doubt this was intention. Maybe there should pop up a warning too, especially to avoid confusion with implicit multiplication "2(x)". Or maybe the implicit multiplication shoud be abandoned (IMO preferable).
Another case are the results of "f(x)" while "f:=2/3", "f:=π", "f:=∞".

P.S. How will "((x->x)+x)(3)" be handled after your fix? Does it differ from "((y->y)+x)(3)"?