make_fun_from_list(lst)lst
list(a=c(1,2), b=3) into
a function that returns 'a' when given 1 or 2 as
argument, 'b' when given 3 and otherwise gives back its
argument unchanged. This is a convenience function to make it possible to
specify onto mappings using lists. The map_*
functions use it internally, but you might find a a use
for it.