Split string at nth occurrence of a given character

Question

Is there a Python-way to split a string after the nth occurrence of a given delimiter?

Given a string:

\'20_231_myString_234\'

It s

Answer 1

I thought I would contribute my two cents. The second parameter to split() allows you to limit the split after a certain number of strings:

def split_at(s, delim, n):
    r = s.split(delim, n)[n]
    return s[:-len(r)-len(delim)], r

On my machine, the two good answers by @perreal, iterative find and regular expressions, actually measure 1.4 and 1.6 times slower (respectively) than this method.

It's worth noting that it can become even quicker if you don't need the initial bit. Then the code becomes:

def remove_head_parts(s, delim, n):
    return s.split(delim, n)[n]

Not so sure about the naming, I admit, but it does the job. Somewhat surprisingly, it is 2 times faster than iterative find and 3 times faster than regular expressions.

I put up my testing script online. You are welcome to review and comment.