Function to truncate data after a certain number of characters?

In the Mockaroo data generator I was wondering if there is a function or way that truncates generated data after a certain number of characters.

For example I use the product name generator to generate columns of random products but my columns only have a max character limit of 15. So I would use this function to strip away any remaining characters after 15.

So this string that is 22 characters long
ABCDEFGHIJKLMNOPQRSTUV

would be truncated down to 15 and look like this instead
ABCDEFGHIJKLMNO

I ended up finding the answer to my own question what ended up working for me was using this syntax

this[0,14]