Question

I’d like to know if one can write the following statement in one line:

new = ''
for char in text:
    if char in blacklist:
        new += ' '
    else:
        new += char

I tried but I get syntax error:

new = ''.join(c for c in text if c not in blacklist else ' ')

I know is not better or prettier, I just want to know if it’s possible.

Answer 1

You’re using your in-line conditional in the wrong place (it’d work if you didn’t have the else ' ' there, as then it’d just be a filter on the iterable). As it is, you’ll want to do it this way:

new = ''.join(c if c not in blacklist else ' ' for c in text)

You could also do it like this if you wanted:

new = ''.join(' ' if c in blacklist else c for c in text)