On Jun 22, 2009, at 5:58 AM, Lowell Thomas wrote: > Terence Parr wrote: >> Has anyone thought of parsing backwards from the end towards the >> detected error location? If you parse forwards and backwards you >> might >> be able to zoom in on a problem area. Of course if there are lots of >> errors following the first one, it won't help you too much. It's sort >> of what a human does though, isn't it? We look down a few tokens and >> work our way back up to see if we can make sense of things. >> >> The other thing I wondered about. Can we launch a whole bunch of >> threads using multiple core to sniff the input to improve error >> analysis? Maybe we launch parsers at multiple points in the input >> stream and then use the interpretation that yields the fewest errors. >> >> Just random thoughts. Let's use those cores, man! > > Just some ruminations here.
> > > Maybe I’m being too pessimistic here but I really don’t hold out a > lot of > hope for automated debugging of grammars. An algorithm writes the > parser but > a human writes the grammar. There is no algorithm I know of that can > take a > spoken-word specification and generate a grammar. And fixing a > defective > grammar is more of the same type of human activity. Until algorithms > can > generate grammars I don’t think algorithms will be more than modestly > helpful in finding and analyzing errors and printing cogent error > messages. > This reasoning is not original to me. It is essentially the same > argument as > Frederick P. Brooks, Jr.’s (“The Mythical Man-Month”) famous and > controversial “No silver bullet” hypothesis. Hi Lowell. I was talking about syntax error reporting and parser recovery at runtime not debugging :) Ter _______________________________________________ PEG mailing list PEG@lists.csail.mit.edu https://lists.csail.mit.edu/mailman/listinfo/peg
