Re: 199.15

[Robert Bruce Findler <robby@cs.rice.edu>]

At 8:21 PM -0600 6/18/01, Matthew Flatt wrote:
>  * Added `error-print-source-location', which controls whether error
>    messages include source information (e.g., line and column, actual
>    expression). Turning off source info in the message text provides
>    less cluttered error messages for tools, like DrScheme, that
>    inspect the exception record anyway.

When I asked for this parameter, the intention was that DrScheme 
could avoid printing the source text for error messages that it can 
display the source location via highlighting, since those error 
messages have source location that are actual edit% objects. They 
look like this:

   Welcome to DrScheme, version 199.14d105.
   Language: Beginning Student custom.
   > '(a b)
   quote: expected a name after a ', found something else in 
#<struct:object:derived-from-rep-text%>:80: (quote (a b))
   >

which is not very helpful.

The parameter, as provided, does give me enough flexibility to do 
that. Right now, the parameter is just a boolean that controls error 
formatting. I would like a parameter something like this:

   error-print-source-location : (parameter (exn -> boolean))

that could enable drs to decide, based on the source location of the 
error, if it should be included in the error message.

Of course, I could just turn it off completely for all language 
levels and have some kind of clickback to show the source locations 
for errors in other files, but I'd prefer to have the extra 
flexibility.

Robby