Lowercasing all words except AND

javascript, regex

Solution

You can lowercase every word that's not exactly AND using a negative lookahead:

str = str.replace(/\b(?!AND).+?\b/g, function(s) {
  return s.toLowerCase();
});

Problem

I'm looking for the fastest way to lowercase all letters that aren't a part of AND in a phrase. I want to leave `AND` in its original case, whether it was `and` or `AND` should not change. For example, `barack AND obama` should test equal to `Barack AND Obama` but not `barack and obama`. (notice the case difference in and) Here is one approach, but I wonder if there is a shorter way or rather a way that avoids iterators: ``` var str = 'Barack AND Obama'; // should be barack AND obama after str = str.split(/\s+/g).map(function (s) { return s.toLowerCase() != 'and' ? s.toLowerCase() : s; }).join(' '); ```

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