* Marco Baringer 871w7vm6m8.fsf@arsenic.bese.it : Wrote on Sat, 02 Feb 2008 21:43:43 +0100:
| It's useful to control what slime prints as the condition | message. this can be used, among other ways, to collect and report | dynamic state which is import to understanding the error but isn't | readily available in the condition object. the attached patch adds a | varibale *sldb-condition-printer*, which defaults to | #'format-sldb-condition, to control this.
I've often wanted to reformat the condition message because the defaults set up in *SLDB-PRINTER-SETTINGS* render the condition unreadable [for example: by truncating too much of the message[1]]. These bindings are already in effect by the time SAFE-CONDITION-MESSAGE (which this patch changes) is called.
Note FORMAT-SLDB-CONDITION is merely defined to be (princ-to-string condition)
So even if you write a replacement for MY-FORMAT-SLDB-CONDITION, it will still be truncated by slime when printing the sldb buffer unless you explicitly rebind the printer variables inside the condition printer. Although rebinding is doable, it suggests that what needs to be under user control is really a `SAFE-CONDITION-MESSAGE' to produce the string which sldb will render verbatim, and which is not called with modified printer settings. (Since you have to resort to a princ-to-string in order to get at the condition message _anyway_)
-- Madhu
[1] In CMUCL some additional variables, *DEBUG-PRINT-{LEVEL,LENGTH}* need to be tweaked.