There is a DevTools addon that allows the file, line, function name and argument values at the time an error is logged to the web console. http://davidbruant.github.io/usefulStackTrace/ It would also be useful to see this information in the call stack.

My add-on is received with enthusiasm by devs usually. It's also a differentiating factor. The way I do it today is ridiculously inefficient: The tab is constantly being debugged (with the perf issues we know), I add an onEnterFrame callback to every single frame (I could remove this hack now that we can know ahead of time if an error will be uncaught, yay!). The perf hit is acceptable as an addon and because the users have to opt-in, but it wouldn't be acceptable by default. This can all change with bug 716647. If this bug gets fixed, then it's possible to wait for an error to be thrown, start debugging at this point (and only at this point!), read all the needed information including the value of the arguments (this is somewhat false if the values of argument variables have been changed before the error, but works for the 90% case) and display both the stack trace and the argument values (maybe even make post-mortem closure inspection possible?). Anyway, setting the dependency and maybe revisit when the dependency is fixed.