val error : ?key:scm->?fn_name:string ->string ->scm
error ?key ?fn_name msg throws a Guile scheme error with tag key (defaults to the symbol ocaml-guile) with message msg, originating while executing fn_name.
Returns a dummy Guile scheme value as it does not return.
val catch : tag:scm->( unit -> unit )->( scm->scm-> unit )-> unit
catch ~tag f handler runs f while catching any exceptions of with tag tag. If an exception is caught, the handler handler is called as handler key args.