Efficiently carry out multiple string replacements in Python

Question

If I would like to carry out multiple string replacements, what is the most efficient way to carry this out?

An example of the kind of situation I have encountered

Answer 1

You may find that it is faster to create a regex and do all the replacements at once.

Also a good idea to move the replacement code out to a function so that you can memoize if you are likely to have duplicates in the list

>>> import re
>>> [re.sub('[aeiou]','',s) for s in strings if len(s) > 2]
['a', 'lst', 'of', 'strngs']


>>> def replacer(s, memo={}):
...   if s not in memo:
...     memo[s] = re.sub('[aeiou]','',s)
...   return memo[s]
... 
>>> [replacer(s) for s in strings if len(s) > 2]
['a', 'lst', 'of', 'strngs']