What is the quickest way to extract a value out of a string if I know the text pattern before and after the value?

For example if I want to extract the password value 'foo' from the string 'password=foo&user=bar', then I will look between the text 'password=' and the ampersand.

I know how to do that with a few statements using split() but is there a one-line regex that will do it?

In reply to simple regex question by redss

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