extending list getitem

[Joris Geessels]

I'm trying to extend getitem of a simple list to allow string aliases for indices.

I'm aware that numba doesn't yet support strings. But I was hoping to somehow convert the python strings to integers using @lower_builtin:

@lower_builtin('getitem', types.List, types.Const)

def list_getitem(context, builder, sig, args):

    # get content of const and turn into an integer

However the list_getitem doesn't seem to be called when using a string as index. If I use types.Integer it does get called ( when using an integer as index ).

I do get something similar to work with overload and a separate function:

def idx(s):

     pass

@overload(idx)

def convert_str(s):

      # logic to convert str to idx

@numba.njit

def test_idx():

    lst = [0, 1, 2]

    i = idx("a")

    # works as expected/desired

    return lst[i]

Any ideas?