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Language reviews: D
CodeLongAndPros (1314)

Language review: D

D is a general-purpose programming language with static typing, systems-level access, and C-like syntax. With the D Programming Language, write fast, read fast, and run fast.

It's pretty much C+++ (C++)+

It's strongly, statically typed, has safe pointer usage, built in unit tests, and more.

It was made by Walter Bright in 1999, with the first public version in 2001, and 1.0 in 2007.

Some code examples:

(Compute average line length for stdin)

void main()
    import std.range, std.stdio;

    auto sum = 0.0;
    auto count = stdin.byLine
        .tee!(l => sum += l.length).walkLength;

    writeln("Average line length: ",
        count ? sum / count : 0);

(Invoke external program)

void main()
    import std.exception, std.stdio, std.process;

    auto result = ["whoami"].execute;
    enforce(result.status == 0);

As you can see, D is a very simple, very fast (On par with C++) language, with only a few cons.

  • Phobos (Stdlibs) documentation is hard to understand, unlike Python's or JS'
  • Not a lot of support / documentation for stuff like GUI's
  • No native Replit support yet. (Use this template)

However, not is all bad

Some of the gems in D:

  • Built in unit test support:
int sum(int a, int b)
	return a + b;
void main() 
		assert add(1, 1) == 2;
		assert add(1, 1) != 3;

Total scores:

Usability: 70% (Lacking in GUI bindings)
Ease of development: 80% (Some strange operators)
Documentation: 50% (Good docs, hard to read)

Total score: 66%

Should you use D?

Yes, unless you are doing GUI work (GTK, QT)

DungeonMaster00 (119)

As a person who likes D a ton, it should have a better editor.

For example, when I type in left parenthesis, there is no right parenthesis generated. The same happens for brackets too.

Another thing. I can't blame repl.it for this, but whenever I make a bracket for an if statement or loop, it doesn't indent again automatically. It just keeps track of the indentation level for you.

Honestly, we should consider ourselves lucky that repl.it provides SYNTAX HIGHLIGHTING for D files That's how garbage I think the D editor is in repl.it. Even the C# editor in repl.it is better.

One last note; there are custom D GUI libraries that you can install with the DUB. I just haven't figured out how to get those yet.

Overall, D is still good. But I still believe it can be better, both in the overall language and the repl.it editor.

CodeLongAndPros (1314)

@nk1rwc I’ve added d support to polygott, but until I get hired under replit or can add code, no dice.

TheDrone7 (1263)

That title looked like a type for the emoji :D.

Highwayman (1341)

In fact the whole Phobos library documentation has been generated with DDoc.

So that’s why it’s wonky...

CodeLongAndPros (1314)

@Highwayman The docs are fine, but they lack explanations and examples

Highwayman (1341)

Exactly. It would be somewhat cumbersome to supply those in the code, so they don’t have them.... that’s what I mean :P @CodeLongAndPros

Highwayman (1341)

Wouldn’t it be C++++? (C++)++

CodeLongAndPros (1314)

@Highwayman I think that’s C#


It’s a little lower level than C#.

CodeLongAndPros (1314)

@Highwayman C++++ is more like Java than C++

Highwayman (1341)

I wonder what python is....


DungeonMaster00 (119)

@Highwayman i realised something, dlang is ++c

Highwayman (1341)

In a site full of nerds you have managed to beat us all I applaud and congratulate you XD

CodeLongAndPros (1314)

@HahaYes I have returned from hiatus —read minecraft—, only to enter into another —but I shall return!