How to allow each allowed character in given string to trigger if-statement-CodePudding

I've been searching on here for a bit and nothing seems to really encapsulate my actual issue, being that I want my given string(if its characters fit my criteria) to cause different if statements. The purpose of my code is for each letter to represent a rotation of my string.

example parts['rotate'] = 'Ff'

allowed = ['F', 'f', 'R', 'r', 'B', 'b', 'L', 'l', 'U', 'u', 'D', 'd']

def rotated(parms):
    result = {}
    if ('cube' not in parms):
        result['status'] = 'error: cube is missing!'
    cube = list(parms['cube'])
    if ('rotate' not in parms or parms['rotate'] == ''):
        return rotateF(cube)
    if (parms['rotate'] == 'F'):
        return rotateF(cube)
    if (parms['rotate'] == 'f'):
        return rotatef(cube)
    if (parms['rotate'] != allowed):
        result['status'] = 'error: invalid rotation'
return result

def rotateF(cube):
    rotatedCube = list(cube)
    .....
    rotatedCube = ''.join(rotatedCube)
    return rotatedCube
def rotatef(cube):
    rotatedCube = list(cube)
    ......
    rotatedCube = ''.join(rotatedCube)
    return rotatedCube

And so currently, the return i'm getting is for 'rotate' = 'Ff' :

{'status': 'error: invalid rotation'}

My assumption is that it is because currently, my code only allows for one character at a time when I just wanted to ensure that those were the only allowed characters, not one per string.

CodePudding user response：

The way your rotate function is written is to compare against exactly a specific string, but it seems like you are providing a list of rotations (in python, a string is a list of characters). Try introducing another helper function, splitting rotated in to something like do_single_rotation, and do_all_rotations (I'm leaving out some of the error handling and whatnot as I'm not sure exactly what your goal is for the function to return)

default_rotate_str = 'F'

def do_all_rotations(parms):
    rotate_str = parms.get('rotate', default_rotate_str)
    cube = list(parms['cube'])
    for rotate_command in rotate_str:
        cube = do_single_rotation(cube, rotate_command)
    return cube

def do_single_rotation(cube, rotate_command):
    if rotate_command == 'F':
        return rotate_F(cube)
    if rotate_command == 'f';
        return rotate_f(cube)
    # .... continue
    if rotate_command == 'D':
        rotate_d(cube)
    raise ValueError("unrecognized rotate command")