Feature request: function dependency graph

[sqs]

For answering things like "What are the possible side effects of this function [i.e., does it have os as a transitive dependency?]", "What other libraries use this function?".

This could be a list UI showing the transitive dependencies of a function's code, and the callers of a function grouped by calling library.

(Split off from #2278, related to #2881 and #2882)

[sqs]

From user feedback (https://sourcegraph.slack.com/archives/C0W2E592M/p1553791017004000):

Thank you for reaching out. I didn't actually get what we were looking for from SourceGraph. We need the graph - the function dependency trees and module dependencies - so I was looking for some sort of graph query API but as far as I can see SourceGraph is just a hyperlinked view of the code. Is there a straightforward API that can query the dependency tree? If so can you send me an example of how to use it, e.g. given a Haskell function, list all transitive dependencies?
Just for clarity; I do see the search functionality but that seems to offer just locating code, which does not suffice. It does not give the dependencies of that code.

[macraig]

This feature request is now tracked in Productboard