"suddenly"? Yes it has become popular overnight in 30+ years. I'd chalk it up to two aspects - strongly typed languages that show how to do safe composition at

"suddenly"? Yes it has become popular overnight in 30+ years. I'd chalk it up to two aspects - strongly typed languages that show how to do safe composition at scale, and .... Compositionality at scale.. One example, lambda calculus in which functions are the only "thing" shows that all "abstractions" can be understood as "beta abstraction" ... Which is formally defined. Other paradigms (like OOP) don't provide such a formal abstraction notion. Shameless plug on that "Beta abstraction for bottom up theory building" [1] [1] https://sriku.org/blog/2016/02/06/beta-abstraction-for-bottom-up-theory-building/ https://sriku.org/blog/2016/02/06/beta-abstraction-for-botto...