Add to Chrome
Add to Edge
Add to Firefox
Add to Opera
Add to Brave
Add to SafariWhen comparing D vs C++, the Slant community recommends D for most people. In the question“What is the best programming language to learn first?” D is ranked 28th while C++ is ranked 29th. The most important reason people chose D is:
With few exceptions, D will either compile C code to work exactly as when compiled as C, or it won't compile - it won't quietly change the semantics of C code and give unexpected results. This means that D contains an improved C, as it fails compilation where type safety is missing in C. This allows learning the same machine operations available in C and other low-level languages.
Specs
Question Ranking
Pros
Pro Has an improved C subset
With few exceptions, D will either compile C code to work exactly as when compiled as C, or it won't compile - it won't quietly change the semantics of C code and give unexpected results. This means that D contains an improved C, as it fails compilation where type safety is missing in C.
This allows learning the same machine operations available in C and other low-level languages.
Pro Easy to read and understand code
Pro Doesn't force you to deal with memory management
When you're just starting out, dealing with manual memory management and its bugs is a huge pain! D is garbage collected by default, which removes a huge class of things that could go wrong. And later on, if you decide you don't want or need the GC, you can turn it off.
Pro Very fast compilation
D is usually up to 10 times faster than C++. Having a language that compiles this fast means that you are free to write highly optimized code because of the relatively low cost of experimentation.
Pro Unit testing built-in
D provides unittest blocks to insert code that verifies functions preform their expected behavior and document edge cases. Since these are enabled with a compiler switch, there is no need to teach new programmers how to install new libraries and import modules, instead training on test driven design can start from the very first function.
Pro Provides a powerful data structure on top of C's arrays called slices
D provides a structure that builds on C's arrays called slices. A slice is a segment of an array that tracks the pointer and the length of the segment.
Slices are extremely powerful because they combine the protection of knowing the length of the data with the garbage collector that manages the memory backing that data, thus avoiding most memory corruption issues.
Pro It's a state-of-art evolution of C
Pro Static with type inference
For a new user adding types can feel tedious, and takes focus off the meaning of the code, but they are also important for checking logic. D provides static types, and a good system to infer types, so types are checked when calling functions, but do not need to be specified everywhere, making it feel more dynamic.
Pro Provable purity and immutability
The compiler can check that functions don't have side effects, extremely important for functional programming in concurrent scenarios, and can check immutability.
Therefore, the compiler will prove that your programs are functionally pure and respect immutable data, if you want it to.
Pro Compile-time Function Execution
Pro Built-in Unicode support
Pro Industrial quality
Pro Asynchronous I/O that doesn’t get in your way
Because all types can be treated as objects, all files can call functions in the same manner -- even stdin and stdout. stdout.writeln(); stdin.readln(); file.writeln(); file.readln();
Pro Easy to integrate with C and C++
D practically has the same memory structure as C and C++; all D does it build a structure around that. The entire C standard library is accessible at no cost (syntactic or speed) and it's being worked on allowing the same for the C++ standard library.
Pro Designed for concurrency and parallelism
Supports first-class functionality for both concurrency and parallelism, offered as part of the standard library.
Pro Supports calling functions from types in an object-oriented manner.
if (exists(file)) {} may be written as if (file.exists) {}.
writeln(file); may be written as file.writeln();
isDivisibleBy(10, 2); may be written as 10.isDivisibleBy(2);
writeln(isEven(add(5, 5))); may be written as 5.add(5).isEven().writeln();
Pro Huge language supports most everything
C++ is a large language with an even larger community and following. It has libraries for every kind of task that is possible to do with C++
Pro Powerful memory management
Allows puting large arrays on the "heap" to avoid "stack overflow".
Pro Teaches fundamental OOP
Teaches you to leverage object oriented programming.
Pro Excellent compiler optimization
Both open source compilers (such as Clang and GCC), and proprietary ones (like Intel's and Microsoft's) are very good at analyzing program flow and program optimization. This is mostly due to the widespread usage of C/C++ applications running everything from mobile/desktop/server Operating Systems, to search engines and webserver software, and the demand for performance.
Pro Teaches problem solving
The great STL is the most powerful Data Structure and Algorithms Library. It would benefit you very much in problem solving, your main main way to love programming. The code is much compact compared to Java and C#. No unnecessary classes are in your way; yet when you need classes they are available unlike C. The code runs very fast.
Pro Teaches low-level programming, but doesn't have as many pitfalls as C
Teaches data types, low-level program flow and the so common C-style syntax while not being as much of a pain as C itself.
Pro STD is often updated
The functionalities keep growing throughout the years. C++11 gave us a soft type of garbage collecting with the smart pointers.
Pro C code can be used in C++ code
Most C code will work as C++.
Pro Faster execution of the same algorithms
Because C++ (and its precursor C) are "lower level" than a lot of popular programming languages they are also faster at executing code than Java or C# which require VMs and garbage collection threads.
Pro Universal, portable, best complexity/efficiency trade-off
Pro Best way to understand algorithms
Pro Has lots of library
C++ is mature and everything has standardized library.
Cons
Con Poor adoption even after many years of existence
There's a widely accepted perception of D as a language that has been poorly adopted. Since adoption is driven by perception this becomes a fact. So managers and engineers start becoming nervous in adopting a language that has such a perception among the community and that has been so unsuccessful for so long.
Con Failed at becoming alternative to C or C++
Almost as confused and complicated as C++, but without the popularity and widespread corporate usage. Also failed at becoming a good cross-platform GUI application development language like Object Pascal. Many missed past opportunities, and now newer languages are better alternatives.
Con Lack of vision
D is community-driven and lacks the support of any large corporation. While this increases the amount of talent and engineering abilities of the people working on D, it also brings a severe lack of charisma, leadership and vision.
Con Garbage Collection
Memory is not managed directly.
Con All the downsides of garbage collection without any of its benefits
When D decided to implement garbage collection it instantly alienated a large community of developers (C and C++ programmers). For them, the official policy has been: "Don't want garbage collection? Use D with RAII or manual management style!".
While true, it's also absolutely pointless because there's little to none support for alternate memory management styles in the standard library, which means that a new user will have to start with a language that is stripped down of the core infrastructure.
On the other hand, for those people who want to use garbage collection, the implementation of it is lackluster.
Con Huge language gets in the way of learning
C++ is such an atrociously over-complicated language that its learning curve may get in the way of learning fundamentals. Learning C++ well is a ten-year project, and even experts are frequently surprised by the language.
Con Undefined behavior
Subtle errors can render the entire program "undefined" by the complicated C++ standard. The standard imposes no requirements in such cases. Thus C++ compiler writers are free to ignore the existence of such cases and Bad Things are prone to happen instead. Even experts can't reliably avoid undefined cases in C++, so how can beginners be expected to do so?
Con Tough to learn as the first language
Many of the concepts are hard to grasp if you have no prior programming experience.
Con Module system is not great
C++ uses the #include mechanism provided by C. Which unfortunately is a poor way of accessing the API of a library. Some of the reasons why the module system is weak are:
Compile time scalability: The compiler must preprocess every header included in a file, and every header included in those headers. This process must be repeated for every translation unit in the program. As can be imagined, this doesn't scale very well. For each header added you are increasing the compilation time exponentially.
Fragile: modules included are treated as textual imports by the compiler. This causes all sorts of problems since they are subject to any macro definitions in the time of the inclusion. If any of these macro definitions collide with a name in the library it can break the library API .
Con C++ succombs under its own weight
The years of cramped backward compatibility start to show in the syntax, complexity and very top-heavy language structures. Trying to keep up with far more elegant languages like C# doesn't do C++ any good either, because the committee always seems to be able to mess it up. After numerous years, still no modules... you must be kidding!
Con Painfully slow compilation
Beginners need fast feedback
Con Duplicates C features in incompatible ways
Arrays, strings, pointers, etc. have both C and C++ versions. Sometimes the C++ versions are worse. This is more useless trivia beginners have to sort through.
Con Undefined behaviors and weak limited type safety
Undefined behavior in a program can cause unexpected results, making it hard to debug. With UB, program behavior may vary wildly depending on optimization settings. There are many cases that invoke UB, such as signed overflow, invalid dereferences, large integer shifts, uninitialized variables, etc. C++ allows for non-type safe operations such as logic errors, wild pointers, buffer overflow, etc. UB and type safety issues create a large number of bugs and security vulnerabilities.
Con No two programmers can agree on which 10% subset of C++ to use
C++ is such a huge and complicated language, that programmers have to learn a disciplined subset of it to reliably get anything done. The problem is, no-one can agree on which subset to use and they can't understand each other.
Con Retains nearly all bad habits of C
Con No reflection
C++ objects are frustratingly opaque. This makes debugging especially difficult, something beginners have to do a lot.
Con Memory leaks and segmentation faults
Because C and C++ allow the user direct access to memory and don't provide garbage collection threads, there is a probability that a program may have a "memory leak", which occurs when something a programmer allocated in the heap is not deallocated properly. Also, attempting to dereference memory protected by the operating system causes a segmentation fault and kills the program.
Con Arcane binding rules
Con Incomprehensible operator overloading resoution
Con After all these years of trying, still no decent string library.
Although you have several ways to handle strings, all of them are messy and error-prone, giving birth to many crashes and memory corruptions in the field. It's one of the worst languages ever, if you have to do strings.
Con Bugs easily corrupt the memory you need to find them
You can usually get a core dump, but often the call stack gets completely overwritten. Compilers are not even consistent in how they map the binary objects to code.
Con No way to locate definitions
No modules, just files, and no way to tell where anything came from.
Con Complicated types
Con Standard library missing important features
Con Exceptions incompatible with C++ manual memory management
