How to split a string into multiple variables & if not enough values, assign the variable as a parti-CodePudding

I have this code (Python 3.9):

vdam = {"mirror": 0, "door": 1, "windShield": 2}
vdam2 = list(vdam.items())
vdam3 = [a[0] for a in vdam2]
vdam4 = ' '.join([str(ele) for ele in vdam3])
a, b, c, d, e, f, g = vdam4.split()

I want to split the string into multiple variables but at the same time, if not enough values to be split, all other left variables get assigned as a particular value. The above code generates the error: ValueError: not enough values to unpack (expected 7, got 3)

CodePudding user response：

Append default values to the list to make it contain the number of elements equal to the number of variables. Then assign them.

vdam5 = vdam4.split()
if len(vdam5) < 7:
    vdam5  = [None] * (7 - len(vdam5))
a, b, c, d, e, f, g = vdam5

CodePudding user response：

vdam2-vdam4 are not needed, nor the .split(). List the keys and append enough defaults to handle 0-7 arguments. The final *_ captures the excess items:

>>> vdam = {"mirror": 0, "door": 1, "windShield": 2}
>>> a,b,c,d,e,f,g,*_ = list(vdam.keys())   [None]*7
>>> a,b,c,d,e,f,g
('mirror', 'door', 'windShield', None, None, None, None)

If you have varying defaults, this works by expanding the keys as parameters to the function:

>>> vdam = {"mirror": 0, "door": 1, "windShield": 2}
>>> a,b,c,d,e,f,g,*_ = list(vdam.keys())   [None]*7
>>> a,b,c,d,e,f,g
('mirror', 'door', 'windShield', None, None, None, None)

>>> def func(a=1,b=2,c=3,d=4,e=5,f=6,g=7):
...    return a,b,c,d,e,f,g
...
>>> a,b,c,d,e,f,g = func(*vdam.keys())
>>> print(a,b,c,d,e,f,g)
mirror door windShield 4 5 6 7

Note you could also use func(*vdam4.split()) as well if you have a space-delimited string.

CodePudding user response：

Here is a suggestion

def fit(x,y,z): #x:string, y:expected length, z:replacement value
    while len(x)<y:
        x  =z
    return x

vdam = {"mirror": 0, "door": 1, "windShield": 2}
vdam2 = list(vdam.items())
vdam3 = [a[0] for a in vdam2]
vdam4 = ' '.join([str(ele) for ele in vdam3])
a, b, c, d, e, f, g = fit(vdam4.split(),7,'A')

mirror door windShield A A A A