My current code:
>>> sent=['attachment', '(1.', '=', '+EDT)', 'Details'] >>> [w[1:] for w in sent if w.startswith(('(', '+'))]+[w for w in sent if not w.startswith(('(', '+'))] output:
['1.', 'EDT)', 'attachment', '=', 'Details'] I want it like this:
['attachment','1.', '=','EDT)', 'Details'] maintaining the original order.
I don't want to use re.replace, I just want to use w.startswith().
To use startswith() while maintaining the original order you need to perform the operation inside one list comprehension. We can do that using a conditional expression:
sent = ['attachment', '(1.', '=', '+EDT)', 'Details'] print([w[1:] if w.startswith(('(', '+')) else w for w in sent]) output
['attachment', '1.', '=', 'EDT)', 'Details'] Your code does not work since it is building 2 lists; the first one contains those which start with + or (, and the second one those which don't; these are then catenated in order.
Your code fixed and using a conditional expression properly would read
>>> sent = ['attachment', '(1.', '=', '+EDT)', 'Details'] >>> [ w[1:] if w.startswith(('(', '+')) else w for w in sent ] ['attachment', '1.', '=', 'EDT)', 'Details'] However a better and more powerful option would be to use re.sub here
>>> import re >>> sent = ['attachment', '(1.', '=', '+EDT)', 'Details'] >>> [ re.sub(r'^[+(]', '', w) for w in sent ] ['attachment', '1.', '=','EDT)', 'Details'] The regular expression ^[+(] matches the beginning of string followed by exactly 1 + or (; whatever is matched is replaced with an empty string ''.
On the other hand if you really want removing all leading ( and + characters, no matter how many, use the .lstrip:
>>> sent = ['attachment', '(1.', '=', '+EDT)', 'Details'] >>> [ w.lstrip('+(') for w in sent ] ['attachment', '1.', '=', 'EDT)', 'Details'] This will also replace +(++++((((foo with foo which might or might not be what you wanted.
re module for this - they want to do it with built-in methods. :)
str.lstrip()seems to be what you want.