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Article 15951 of comp.std.c++:


John Max Skaller <maxtal@suphys.physics.su.oz.au> writes

 > Eugene Radchenko wrote:
 > > Why don't use, for instance, cast_d instead od
 > > dynamic_cast (ugh). 
 > 
 >       This is quite deliberate. Bjarne dislikes casts. So do I.
 > He didn't invent new style casts (and RTTI) for your convenience, 
 > he invented them to make sure no one else did.

Hmmm. That is a bit strong.  I find casts of all sorts overused.
There is almost always a better way to write code than one that
involves an explicit type conversion.

However, IMO some casts are essential. Some uses of dynamic_cast are
examples of code that cannot be written conveniently without help
from the language; see D&E for examples. Please remember that you
don't always have source code available so that you can modify classes
to avoid the need for RTTI,and even where it is available you sometimes
prefer not to touch it to minimize maintainance.

 >  Long names were deliberately chosen to discourage use of casts.

That, to make emphasize the seriousness of the operation done with
a cast, and to make sure that casts are relatively easy to find in
a program (``to make casts stand out like a sore thumb'').

One think I have come to dislike about C-style casts is that they
are almost invisible in code. Since they don't look like much,
people get fooled into thinking they don't do much. Also, (T)e is a
shorthand for several logically different operations (type conversion,
reinterpretation of a bitpattern, casting away const, class hierarchy
navigation) and you need to know the type T, the type of e, and the
rules of C++ rather well to know which.

	- Bjarne
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