python - Remove repeating characters from words

Question

I was wondering what is the best way to convert something like "haaaaapppppyyy" to "haappyy".

Basically, when parsing slang, people sometimes repeat characters for added emphasis.

I was wondering what the best way to do this is? Using set() doesn't work because the order of the letters is obviously important.

Any ideas? I'm using Python + nltk.

Answer 1

It can be done using regular expressions:

>>> import re
>>> re.sub(r'(.)1+', r'11', "haaaaapppppyyy")     
'haappyy'

(.)1+ repleaces any character (.) followed by one or more of the same character (because of the backref 1 it must be the same) by twice the character.