Looking at Effective C++ Challenges of C++ Ibrahim Haddad
Monday, July 25, 2005 12:03:59 PM
LinuxPlanet: "Modern" computing platforms like Java and .NET are based on managed environments with garbage collection and extensive collections of standard library functionality. C++ isn't. Why would developers choose
C++ for software systems today?
Meyers: This is a question that I posed to one of the C++ newsgroups recently.
The discussion ran to nearly 250 messages from over 100 different people,
but a few reasons came up repeatedly:
C++ is a multiparadigm programming language, offering support for
procedural programming, object-oriented programming, generic
programming, template metaprogramming, etc. These paradigms can be
freely mixed, so developers are free to choose the approach to a
problem they find most natural. No other mainstream language can make
that claim. Interestingly, I mention this in Item 1 of the new edition
of my book, because recognizing that C++ supports multiple styles of
programming is essential to making effective use of it.
C++ offers programmers control over almost everything, so when they
need to touch the hardware, interface with other languages, control the
details of dynamic memory allocation, etc., they can do it.
Furthermore, when it comes to flat-out performance, well-written C++
still usually beats well-written software in other languages--often
by a substantial margin.
C++ runs almost everywhere, from the smallest embedded systems to the
largest computing clusters. Java may be able to make a similar claim,
but none of the .NET languages (e.g., C#) can, at least not yet.
C++ is already very widely used, so in many cases, continuing to use it
is the most straightforward way to extend an existing system.
C++ isn't controlled by any single corporate interest (such as Sun in
the case of Java or Microsoft in the case of C#).
LP: For programmers migrating from languages such as Java and C#, you suggest
C++ can be a bit of a challenge initially. What do you think is the
biggest hurdle for those programmers to overcome?
Meyers: One of the most challenging aspects of moving from one language to
another is overcoming false assumptions. It's hard to be on the lookout
for trouble if you don't realize that it's possible. For example, C++
objects can sometimes go uninitialized, but, as far as I know, that's
impossible in Java or C#. C++ has a number of things that lead to
undefined behavior, again, something that can't exist in Java or C#. C++
objects can have multiple addresses, which isn't possible in Java or C#.
In the third edition of Effective C++, I mention these things and several
others, because it's important for developers from other languages to
understand when the fundamental behavior of the language is other than
what they are likely to expect. Perhaps that's the biggest hurdle for
such developers: becoming aware of subtle, but fundamental, differences
in behavior in C++ compared to the language they've been using.
