Forum Discussion
Lazy evaluation
Hi Dicken
List.Transform operates on empty list {}, so transformation function (x) => x{0} is never executed resulting empty list.alist{0} directly attempts to access first element of an empty list which immediately raises an index out of range error
alist = {{}} contains one element (an empty list). List.Transform execute once passing {} as x and x{0} fails because inner list is empty, so tr becomes an error. alist{0} returns first element of the outer list which is the empty list {}, so no error
hi, (x) => x{0} is applied to each element of the list, not the list itself. That's why List.Transform with empty list { } returns the same empty list (nothing to transform) while List.Transform with { { } } returns ... no, not error but the list with single element {error}. And It has nothing to do with lazy / eager evaluation.