completion: expression inside brackets should be any variable

[rcoreilly]

From @rohrlich in #125

completion inside brackets should be finding all vars but in code below where you see "..." the completion list is the single item "splits" until you type some character which brings up the properly filtered list. My recollection is that we don't automatically populate if there are more than N items but forcing the list should not be displaying a single item.

splits := strings.SplitAfterN(s, "/", cnt+1)
ss.SimMat.Rows[r] = splits[...

[rcoreilly]

the tradeoff here is that an on-demand completion in splits[... shows the type information for this item, which is pretty handy at that point. and usually you have at least a first letter, so that transitions to the complete the filler mode.