I'm curious to know if there is any history between the usages of "yeah-no" and "no-yeah" in English, and if the usage of the two terms or an equivalent is used in other languages. Also, is there a distinct difference in meaning between the two phrases in terms of usage and context or are they interchangeable? I've noticed a lot of people including myself tend to use both in everyday language. Example usage:
Person A: I think pizzas are pretty awesome.
Person B: No-yeah, pizzas are definitely awesome.