syntax: exception-always always expression
evaluate nullary \"always\" after expression even if an exception occurred
procedure: exception-display-guile key a ->
procedure: exception-display-guile-r6rs key a ->
display information about an r6rs exception object received by guile catch
syntax: exception-intercept on-exception expression
evaluate \"on-exception\" if an exception occurred in expression
syntax: exception-intercept-if expression on-exception no-exception
evaluate \"on-exception\" if an exception occurred in expression.
evaluate \"no-exception\" if no exception occurred and return the result of expression
procedure: exception-printer port key args punt ->
variable: sph-exception-description