dict comprehension

Question

Is their a way to redo the following code using dict comprehension

l = ['abcd','bcd','fgh','azxs']
d= {}
for x in l:
if x[0] not in d:
d[x[0]] = [x]
else:
d[x[0]].append(x)
print(d)

i tried the following way but it is throwing an error

l = ['abcd','bcd','fgh','azxs']
A= {x[0]:[x] if x[0] not in A else x[0].append(x) for x in l}

the expected output is dictionary :
{'a': ['abcd', 'azxs'], 'b': ['bcd'], 'f': ['fgh']}

Answer 1

I think your approach with for...loop is more suitable for such purpose.

If I understood it correctly, comprehension is good for creating a dictionary item, or replacement of existing dictionary item's value. But here you rather want to add something to the item's value than to replace it with something else.

Answer 2

Ipang I was just exploring the list and dict comprehension , and curious to know whether this problem can be done by dictionary comprehension
thanks for your reply