Don wrote:
Paul D. Anderson wrote:
Sounds like someone needs a strong dose of D!!
http://java.dzone.com/articles/why-java-doesnt-need-operator
The comments bounce between "operator overloading is always bad
because you can do idiotic things with it" and "operator overloading
is essential because sometimes you really need it".
How about a language where operator overloading is available for the
cases where you do really need it, but isn't available in general?
Hmmm...
Paul
He says he doesn't like it because:
The number of operators that you can overload is very small and each of
them is attached to very specific semantics that makes little sense
outside the realm of scalars and of a few other specialized mathematical
concepts (e.g. matrices).
Bingo! That's what operator overloading is for. **Don't overload
arithmetic operators unless you are doing arithmetic.** I think the main
problem with operator overloading in C++ is that that point wasn't
explained well at all. The D spec could probably do a better job of it,
but at least the ~ operator removes the temptation for people to use +
to mean concatenation.
This reminds me of something I did at work. C# 2.0 has no builtin syntax
for associative arrays, and we needed to create a lot of dictionaries of
string -> object. We came up a little class with operator overloads:
operator[string,object] added a dictionary entry and returned the
dictionary builder. But when you're done with that, you still need to
convert to a dictionary. So we added an operator overload for this.
Now we format strings like:
_formatter.Format("${hello} ${world}", -Using.Values["hello",
helloObject]["world", worldObject]);
