On 5/20/13 1:03 PM, Peter van der Zee wrote:
> This may not be the right place, but what should browsers do when an error
> is raised in an area of the translated code? As a dev I would not like to
> be sent to a wild goose chase, only to find out later that the error wasn't
> due to my code but due to the way it was translated.
> Should the browser make note of this (can it even know?)? Should it just
> let the user figure this out?
I'm not 100% sure what kind of errors you mean, can you give an example?
Firefox's debugger's "pause on exceptions" feature should work perfectly
well with source maps, and if you can find a case where it doesn't then
please file a bug ;)
If the compiler creating the source map has done a poor job, there isn't
much we can do, and that is really the compiler's responsibility.
If there is an error at a null mapping, it is generally either an error
in the prologue generated by the compiler, or a bad source map. Once
again, not really the browser's responsibility, but it would be nice if
the user had some indication of what is going on.
At Mozilla, we made the architectural decision not to source map stack
objects) due to potential security issues. On top of that, we don't have
to block js execution until we have a source map whenever we get errors
and are creating Error() objects. Furthermore, it avoids having whether
or not you can fetch a source map from changing the path of running code
if it is trying to reflect on the stack frames. If this is the scenario
you are talking about, I'd suggest porting the source-map-support npm
module to the web.
Hope this helps,