How can I refer to several aggregation functions in a data.table dcast?

Question

I want to put the data.table function dcastin a function that can handle its own number / order of aggregate functions. This is why I need to pass aggregated functions as function parameters dcast. Parameters must be defined out dcast. How can i do this?

This works well, but I want to define aggregate functions outside of dcast.

dt = data.table(x = sample(5, 20, TRUE), y = sample(2, 20, TRUE), 
                z = sample(letters[1:2], 20, TRUE), d1 = runif(20), d2 = 1L

dcast(dt, x + y ~ z, fun = list(sum, min), value.var = "d1")

I tried this method:

func <- list(sum, min)

dcast(dt, x + y ~ z, fun = func, value.var = "d1")

Then I get this error message:

Error in eval (expr, envir, enc): could not find function "func"