From mboxrd@z Thu Jan 1 00:00:00 1970 X-Spam-Checker-Version: SpamAssassin 3.4.4 (2020-01-24) on polar.synack.me X-Spam-Level: X-Spam-Status: No, score=-1.3 required=5.0 tests=BAYES_00,INVALID_MSGID autolearn=no autolearn_force=no version=3.4.4 X-Google-Language: ENGLISH,ASCII-7-bit X-Google-Thread: fac41,b87849933931bc93 X-Google-Attributes: gidfac41,public X-Google-Thread: 109fba,b87849933931bc93 X-Google-Attributes: gid109fba,public X-Google-Thread: 103376,b87849933931bc93 X-Google-Attributes: gid103376,public X-Google-Thread: 1108a1,b87849933931bc93 X-Google-Attributes: gid1108a1,public X-Google-Thread: f43e6,b87849933931bc93 X-Google-Attributes: gidf43e6,public X-Google-Thread: 114809,b87849933931bc93 X-Google-Attributes: gid114809,public From: bobduff@world.std.com (Robert A Duff) Subject: Re: Exceptions as objects (was Re: What is wrong with OO ?) Date: 1997/01/29 Message-ID: #1/1 X-Deja-AN: 212940895 references: <5acjtn$5uj@news3.digex.net> <32e9e445.163056932@library.airnews.net> organization: The World Public Access UNIX, Brookline, MA newsgroups: comp.lang.c++,comp.lang.smalltalk,comp.lang.eiffel,comp.lang.ada,comp.object,comp.software-eng Date: 1997-01-29T00:00:00+00:00 List-Id: In article , Piercarlo Grandi wrote: >Actually, it's not *my* scheme, it has been known for thirty years or Yes, I realize you didn't invent it. ;-) >...Dynamically scoped identifiers are usuful for a number of >cases where actions must depend on the program context; dynamically >scoped variables, not just procedures, are very useful too. Non local >control transfers are also very useful in their own right. OK, I'll buy that much. But how do you write an ``exception handler'' that catches a whole class of related exceptions. (E.g. division by zero might raise "Divide_Error", and the caller can choose to handle "Divide_Error" or "Arithmetic_Error" (which includes Divide_Error), or "Any_Exception", or whatever.) - Bob