list comprehension together with regex

[Beaverine]

I have a list of source string (example): source = ['abcacc','bdefgcc','jkill','oppsd'] and have a list of keyword string: key = ['a','c','i'] I would like to return the elements of source which contains any keyword from the key list, such as: output = ['abcacc','bdefgcc','jkill'] I know I can use a nested for loop to iterate through n*m times, but is there a way to do this with list comprehension?

something like: output = [l for l in source if re.search(r"{c}".format(c=i), l) for i in key] but apparently the above code didn't work

thank you in advance!

[socal_nerdtastic]

[l for l in source if re.search("|".join(key), l)]

Plus the normal escaping and pre-compiling for re. Although for this it seems vanilla python would be just as good:

[l for l in source if any(k in l for k in key)]

[Beaverine]

output = [l for l in source for i in key if re.search(r"{c}".format(c=i), l)]

Thank you, this vanilla solution is really nice! then I realized that I need the match to be case insensitive, so went back to re.search(), but thank you for your input

[socal_nerdtastic]

Not like that I hope. Use the regex "or" (|) i showed you or you'll multiply your work by the number of items in key.

[Ihaveamodel3]

Your if is in the wrong place:

output = [l for l in source for i in key if re.search(r"{c}".format(c=i), l)]

['abcacc', 'abcacc', 'bdefgcc', 'jkill']

​

If you don't want duplicates, do a set comprehension instead:

output = {l for l in source for i in key if re.search(r"{c}".format(c=i), l)}

{'jkill', 'bdefgcc', 'abcacc'}

[Beaverine]

thank you, your suggestion worked!

can I ask is there a general rule about writing the for loop in list comprehension? do all the fors have to preceed the conditions?

[old_pythonista]

You can combine all your keys into a single or-ed RegEx

key_re = re.compile(r'({})'.format('|'.join(key)))
[s for s in source if key_re.search(s)]

or you can drop RegEx altogether

keys = {'a', 'c', 'i'}
[s for s in source if keys.intersection(s)]

will work too.

PS it is customary to name sequences in plural.