Re: Exploring a code base?

[Dmitry Gutov <dgutov@yandex.ru>]

On 27.10.2020 13:38, Yuri Khan wrote:

> Basically what I’m doing is traversal of a graph, where nodes are type
> and function definitions, and edges are relationships such as
> “function <calls> function”, “function <accepts> type”, “function
> <returns> type”, “type <derives from> type”, “type <aggregates> type”,
> etc.
> 
> When the change I’m doing is not very invasive, the affected subgraph
> fits completely in my head. However, when it doesn’t, I find myself
> having to record my traversal state. I create an Org buffer and
> manually maintain a queue of nodes, marking those I haven’t yet
> visited with TODO and those I have with DONE. Then I pick the first
> TODO, grep or xref-find-references on it, add any relevant nodes to
> the queue, make the necessary changes in the code, and mark the node
> DONE. Repeat until no TODO.

Speaking of Xref, we could add some new commands: to remove items from 
the list, to undo removals. And a stacking for searches, so you could go 
back to the previous search result. Not sure how much that will help.

> This is rather tedious. It feels like there should exist a better way,
> maybe with a visualization of the graph structure.
> 
> What do you use to explore and map a code base and perform extensive
> changes on it?

I don't have a solution, personally, and I usually work in a dynamic 
language where this isn't a very feasible thing to do.

But the feature in question sounds intriguing. Here's a couple things 
for C/C++ I found with a brief search:

* https://github.com/beacoder/call-graph uses GNU Global. It has a 
tree-based Emacs interface. Could be a bit immature/use some help with 
development, looking at the issues list.

* Here's a recipe for a graphical call graph: 
https://stackoverflow.com/a/5373814/615245 It is probably not exactly 
what you wanted, but the intermediate created by Clang could serve as a 
better data source than Global if someone tried to create a new Emacs 
based UI for this.

If you find any of this useful, please share your experience.