Why is this comment being downvoted? The nodes of a flow graph (usually) are equivalent to pure functions. The graph represents chaining of those functions and

Why is this comment being downvoted? The nodes of a flow graph (usually) are equivalent to pure functions. The graph represents chaining of those functions and the ports of the nodes are their type signatures. There is a comment in parallel that correctly states "getting down" is a gap or difficult. This maps to the fact that functional programming paradigms are easier to use higher up and deep down it somehow gets imperative on the way, and be it only in the compiler...