Hello schemers, the guard expression from (rnrs) would be a lot more useful if it managed to catch all exceptions. As it is now, some errors will bypass the guard: scheme@(guile-user)> (import (rnrs)) scheme@(guile-user)> (guard (exn (else #f)) (fx+ #f #f)) $1 = #f scheme@(guile-user)> (guard (exn (else #f)) (fx+)) ;;; :3:0: warning: possibly wrong number of arguments to `fx+' rnrs/arithmetic/fixnums.scm:153:2: In procedure fx+: rnrs/arithmetic/fixnums.scm:153:2: Wrong number of arguments to # The background is that I'm working on a program that intentionally calls procedures with bad arguments, and it needs to determine if the procedure accepted the arguments or not. Ideally the object raised would be a proper and correct R6RS condition object, but I suspect that most of the existing Guile code doesn't raise conditions like that. I think it would be a step forward if guard at least caught the exception, even if the condition object might not be very useful. Tested with Guile 2.0.9.40-824b-dirty. Regards, -- Göran Weinholt "Bring me back // to a story left untold // so we can write the ending." -- Aly & Fila feat. Jwaydan - We Control The Sunlight