Is dynamic_cast safe?

Article View: comp.std.c++

Article #3520

#3520

From: Lars Farm
Date: Tue, 27 Feb 1996 16:01

22 lines
1403 bytes

     5.2.6  Dynamic cast                           [expr.dynamic.cast]
   ...
   6 Otherwise,  v shall be a pointer to or an lvalue of a polymorphic type
   ...
What should happen when 'v' is not a pointer to or an lvalue of a
polymorphic type? return 0? crash? throw bad_cast? undefined?
   ...
   8 The  run-time  check  logically  executes  like  this: 
     [...]  Otherwise, the run-time  check fails.

If fail means undefined, why not require that it returns 0?

--
Lars Farm, lars.farm@nts.mh.se


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From: lars.farm@nts.mh.se (Lars Farm)
Newsgroups: comp.std.c++
Subject: Is dynamic_cast safe?
Date: 27 Feb 1996 16:01:15 GMT
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