What is the proper regular expression for an unescaped backslash before a character?

Question

Let\'s say I want to represent \\q (or any other particular \"backslash-escaped character\"). That is, I want to match \\q but not \\\\q

Answer 1

Leon Timmermans got exactly what I was looking for. I would add one small improvement for those who come here later:

/(?

The additional ?: at the beginning of the (\\\\) group makes it not saved into any match-data. I can't imagine a scenario where I'd want the text of that saved.