Helper to map a chain of functions in order to a given list.

mapchain.py

def mapchain(*functions_then_list):
    '''
    mapchain(f..fn, list)
    Map the functions in sequence from left to right across list
    mapchain(f1, f2, f3, f4, list) => map(f4, map(f3, map(f2, map(f1, list))))
    '''
    if len(functions_then_list) < 2: raise TypeError("mapchain(f..fn, list) requires at least one function and a list")
    ops, items =  functions_then_list[0:-1], functions_then_list[-1]
    if not reduce(lambda a, b: a and b, map(callable, ops), True): raise TypeError("All but the list must be callable")
    return reduce(lambda a, b:\
                      map(b, a),
                  ops,
                  items)