--- /dev/null
+
+Type and Pointer Analysis to-do list
+====================================
+
+Alan Donovan <adonovan@google.com>
+
+
+Overall design
+--------------
+
+We should re-run the type and pointer analyses periodically,
+as we do with the indexer.
+
+Version skew: how to mitigate the bad effects of stale URLs in old pages?
+We could record the file's length/CRC32/mtime in the go/loader, and
+refuse to decorate it with links unless they match at serving time.
+
+Use the VFS mechanism when (a) enumerating packages and (b) loading
+them. (Requires planned changes to go/loader.)
+
+Future work: shard this using map/reduce for larger corpora.
+
+Testing: how does one test that a web page "looks right"?
+
+
+Bugs
+----
+
+(*ssa.Program).Create requires transitively error-free packages. We
+can make this more robust by making the requirement transitively free
+of "hard" errors; soft errors are fine.
+
+Markup of compiler errors is slightly buggy because they overlap with
+other selections (e.g. Idents). Fix.
+
+
+User Interface
+--------------
+
+CALLGRAPH:
+- Add a search box: given a search node, expand path from each entry
+ point to it.
+- Cause hovering over a given node to highlight that node, and all
+ nodes that are logically identical to it.
+- Initially expand the callgraph trees (but not their toggle divs).
+
+CALLEES:
+- The '(' links are not very discoverable. Highlight them?
+
+Type info:
+- In the source viewer's lower pane, use a toggle div around the
+ IMPLEMENTS and METHODSETS lists, like we do in the package view.
+ Only expand them initially if short.
+- Include IMPLEMENTS and METHOD SETS information in search index.
+- URLs in IMPLEMENTS/METHOD SETS always link to source, even from the
+ package docs view. This makes sense for links to non-exported
+ types, but links to exported types and funcs should probably go to
+ other package docs.
+- Suppress toggle divs for empty method sets.
+
+Misc:
+- The [X] button in the lower pane is subject to scrolling.
+- Should the lower pane be floating? An iframe?
+ When we change document.location by clicking on a link, it will go away.
+ How do we prevent that (a la Gmail's chat windows)?
+- Progress/status: for each file, display its analysis status, one of:
+ - not in analysis scope
+ - type analysis running...
+ - type analysis complete
+ (+ optionally: there were type errors in this file)
+ And if PTA requested:
+ - type analysis complete; PTA not attempted due to type errors
+ - PTA running...
+ - PTA complete
+- Scroll the selection into view, e.g. the vertical center, or better
+ still, under the pointer (assuming we have a mouse).
+
+
+More features
+-------------
+
+Display the REFERRERS relation? (Useful but potentially large.)
+
+Display the INSTANTIATIONS relation? i.e. given a type T, show the set of
+syntactic constructs that can instantiate it:
+ var x T
+ x := T{...}
+ x = new(T)
+ x = make([]T, n)
+ etc
+ + all INSTANTIATIONS of all S defined as struct{t T} or [n]T
+(Potentially a lot of information.)
+(Add this to guru too.)
+
+
+Optimisations
+-------------
+
+Each call to addLink takes a (per-file) lock. The locking is
+fine-grained so server latency isn't terrible, but overall it makes
+the link computation quite slow. Batch update might be better.
+
+Memory usage is now about 1.5GB for GOROOT + go.tools. It used to be 700MB.
+
+Optimize for time and space. The main slowdown is the network I/O
+time caused by an increase in page size of about 3x: about 2x from
+HTML, and 0.7--2.1x from JSON (unindented vs indented). The JSON
+contains a lot of filenames (e.g. 820 copies of 16 distinct
+filenames). 20% of the HTML is L%d spans (now disabled). The HTML
+also contains lots of tooltips for long struct/interface types.
+De-dup or just abbreviate? The actual formatting is very fast.