Re: Guile top-level functions

[Neil Jerram]

Kevin Ryde wrote:
> Mike Gran <address@hidden> writes:
>
> > I had thought it would be neat to color code them by module.  Is there
> > a way from the C API to find out the filename and line number of a SCM
> > procedure?
>
>
> I was wanting that the other day too, from the procedure would be
> good, from the module variable would be even better.  The reader gets
> the information, but is it thrown away?

Not if you set the 'positions read option, i.e.

(read-enable 'positions)

Then source location information is saved in a weak hash table 
(scm_source_whash, I think) indexed by each read pair.  Given a read 
expression X, you can get its filename, line and column from

(source-property X 'filename)
(source-property X 'line)
(source-property X 'column)

I'm now sure, though, how to access this for a given procedure; I 
suspect there are two problems:

- procedure-source may return a new unmemoized copy of the procedure's 
source, not the original source, and without source properties attached

- it may be impossible to enable the 'positions option early enough in 
boot-9.scm to catch everything that you want to catch.

I hope this is some help, though.

        Neil