Combining pre-defined functions

Dear ROOT developers,

Can’t ROOT create a compound of built-in functions
by one line like
TF1 gg(“gg”, “gaus+gaus”) ?

I know any kind of function can be defined
but we need to start coding from the definition of Gaussian.
In PAW, it is very easy to combine pre-defined funtions
in histogram fitting etc.


see example in tutorial multifit.C

see also docs of TF1 and TFormula