WAWalterBright·Dec 21, 2022
> difficult to parse
Not really. Just create a bit mask.
https://github.com/dlang/dmd/blob/master/compiler/src/dmd/cp...
In Checked Cdlang
dmd
D2011–2026
dlang / dmd
dmd
dmd D Programming Language compiler
33Distinct people
93Mentions
2Explicit recommenders
3.3KGitHub stars
What to know before exploring
What it is
dmd D Programming Language compiler
GitHub
Where it is used
No documented product use was verified in the last source check.
What people are saying
Here's one of my favorite uses for it. I used to write a separate program to generate static tables. With compile time function execution, this was no longer necessary. Here's…
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Also in these discussions
- digitalmars/compiler · linked in 2 of the same discussions
Mentioned in the same Hacker News threads. That is not proof they are substitutes.
This week on Hacker News
Nov 8–Nov 15 UTC · Direct repository links and separately labeled related project stories. Indexed through 11/15/2026, 9:28:18 AM UTC.
No direct repository links were found in the indexed HN discussions over the past seven days. Older discussions are available below.
Mentions over time
HN mentions by year93 dated mentions
Observed mentions: 2011-06-15 09:08:48 UTC to 2026-08-23 10:26:49 UTC.
* An incomplete calendar period is marked with an outlined bar. Its count is not directly comparable with a full period.
Counts come from the repository’s dated source evidence. Index cutoff: 2026-11-02 08:16:59 UTC.
View mention counts and date ranges
| Period | Start (UTC) | End (exclusive, UTC) | Mentions | Submissions | Comments |
|---|---|---|---|---|---|
| 2011 | 2011-01-01 00:00:00 UTC | 2012-01-01 00:00:00 UTC | 1 | 0 | 1 |
| 2012 | 2012-01-01 00:00:00 UTC | 2013-01-01 00:00:00 UTC | 1 | 0 | 1 |
| 2013 | 2013-01-01 00:00:00 UTC | 2014-01-01 00:00:00 UTC | 2 | 0 | 2 |
| 2014 | 2014-01-01 00:00:00 UTC | 2015-01-01 00:00:00 UTC | 5 | 1 | 4 |
| 2015 | 2015-01-01 00:00:00 UTC | 2016-01-01 00:00:00 UTC | 1 | 0 | 1 |
| 2016 | 2016-01-01 00:00:00 UTC | 2017-01-01 00:00:00 UTC | 2 | 0 | 2 |
| 2017 | 2017-01-01 00:00:00 UTC | 2018-01-01 00:00:00 UTC | 3 | 0 | 3 |
| 2018 | 2018-01-01 00:00:00 UTC | 2019-01-01 00:00:00 UTC | 5 | 0 | 5 |
| 2019 | 2019-01-01 00:00:00 UTC | 2020-01-01 00:00:00 UTC | 6 | 0 | 6 |
| 2020 | 2020-01-01 00:00:00 UTC | 2021-01-01 00:00:00 UTC | 17 | 2 | 15 |
| 2021 | 2021-01-01 00:00:00 UTC | 2022-01-01 00:00:00 UTC | 12 | 2 | 10 |
| 2022 | 2022-01-01 00:00:00 UTC | 2023-01-01 00:00:00 UTC | 14 | 1 | 13 |
| 2023 | 2023-01-01 00:00:00 UTC | 2024-01-01 00:00:00 UTC | 2 | 0 | 2 |
| 2024 | 2024-01-01 00:00:00 UTC | 2025-01-01 00:00:00 UTC | 11 | 1 | 10 |
| 2025 | 2025-01-01 00:00:00 UTC | 2026-01-01 00:00:00 UTC | 6 | 2 | 4 |
| 2026 (partial) | 2026-01-01 00:00:00 UTC | 2027-01-01 00:00:00 UTC | 5 | 0 | 5 |
What Hacker News says
14 sources> You can’t actually write a C parser
Actually, you can. I added one to the D compiler, and dubbed it ImportC. With ImportC, in your D code you can write:
import stdio;
and if there's a stdio.h file, the D compiler will read the .h file, parse it, and present the ABI to it in a D-ish manner to your D code. Here it is:
https://github.com/dlang/dmd/blob/master/compiler/src/dmd/cp...
It's so darned useful I expect other languages will do it, too. People were skeptical at first, but it's a solid gold productivity enhancer.
In C isn't a programming language anymoreHere's a one file disassembler for x86 and its successors:
https://github.com/dlang/dmd/blob/master/compiler/src/dmd/ba...
The fun thing to do with it is send it your name and have it disassemble it.
(I use it to check the object code generated by the compiler. Instead of pretty-printing the instruction stream, it disassembles the binary object code. This helps to find mistakes in either the code generation or the disassembler, as they must match.)
Anyhow, feel free to incorporate it into your obj file dumper, exe file dumper, debugger, or any tool that can benefit by examining code.
In A 23-byte “hello, world” program assembled with DEBUG.EXE in MS-DOSThe C compiler I wrote last year:
https://github.com/dlang/dmd/blob/master/compiler/src/dmd/cp...
is vastly different from the one I wrote in the 1980s:
https://github.com/DigitalMars/Compiler/blob/master/dm/src/d...
My original evil plan was to recycle the old one, but I just couldn't.
In The Business Impact of Code Quality> Zig also takes this approach
D took the much more fun way, which is to implement a new C parser from scratch and tweak the D lexer and semantics to handle the differences of C. It's not too bad, about 5000 lines of D:
https://github.com/dlang/dmd/blob/master/compiler/src/dmd/cp...
In C2Rust TranspilerHere, a GC implemented in Oberon, a GC enabled systems programming language,
https://people.inf.ethz.ch/wirth/ProjectOberon/Sources/Kerne...
For something more modern in D, also a GC enabled systems programming language,
https://github.com/dlang/dmd/tree/master/druntime/src/core
In I like OdinAnd now you can embed a free x86 disassembler in your program.
https://github.com/dlang/dmd/blob/master/compiler/src/dmd/ba...
The cool thing to do with it is add it to your favorite text editor as a command - highlight some of your text and disassemble it! Great party game - what is your name disassembled? Valid code, or are you a seg fault?
In Yes, the 8086 wanted to be mechanically translatable from the 8080, butPeople say that dmd's backend is terrible and undocumented, but I don't know what they're talking about:
https://github.com/dlang/dmd/tree/master/src/dmd/backend
In Diving into GCC Internals> errno: look up errno names and descriptions
I like this. Reminds me of a couple very useful things I've done:
1. Add a -man switch to command line programs. This causes a browser to be opened on the web page for the program. For example:
dmd -man
opens https://dlang.org/dmd-windows.html in your default browser.
2. Fix my text editor to recognize URLs, and when clicking on the URL, open a browser on it. This silly little thing is amazingly useful. I used to keep bookmarks in an html file which I would bring up in a browser and then click on the bookmarks. It's so much easier to just put them in a plain text file as plain text. I also use it for source code, for example the header for code files starts with:
/*
* Takes a token stream from the lexer, and parses it into an abstract syntax tree.
*
* Specification: $(L
Read the rest
INK2 https://dlang.org/spec/grammar.html, D Grammar)
*
* Copyright: Copyright (C) 1999-2020 by The D Language Foundation, All Rights Reserved
* Authors: $(LINK2 http://www.digitalmars.com, Walter Bright)
* License: $(LINK2 http://www.boost.org/LICENSE_1_0.txt, Boost License 1.0)
* Source: $(LINK2 https://github.com/dlang/dmd/blob/master/src/dmd/parse.d, _parse.d)
* Documentation: https://dlang.org/phobos/dmd_parse.html
* Coverage: https://codecov.io/gh/dlang/dmd/src/master/src/dmd/parse.d
*/
and I'll also use URLs in the source code to reference the spec on what the code is implementing, and to refer to closed bug reports that the code fixes.
Very, very handy!
I like to use compile time code to generate fixed tables, like these:
https://github.com/dlang/dmd/blob/master/src/dmd/backend/ope...
Notice how a static immutable array is created by a lambda at compile time. The lambda never appears in the executable. Before D, I'd use a separate C executable to generate the tables, which were then #include'd.
The lambdas can also include sanity checks:
https://github.com/dlang/dmd/blob/master/src/dmd/backend/ope...
In Compile-Time Sort in Dhttps://github.com/dlang/dmd/tree/master/test
I work on D too, feel free to email.
In Why I Like DI originally underestimated the value of Open Source, which was definitely a mistake. Now I do everything in Open Source. The latest was releasing my disassembler, originally written in 1982, under a Boost License. (It may be old, but it disassembles the latest Intel instruction sets.)
It's now part of the dmd D compiler. Just throw the -vasm switch, and it'll display the generated code on the console.
I see many uses for a freely available disassembler. For example, you can add it to your favorite text editor! Admit it, you've always wanted to disassemble your text.
https://github.com/dlang/dmd/blob/master/src/dmd/backend/dis...
In Why I Like DHi!
Massively predictable comment making noises about Symantec code-dumping QEMM, DESQview and DESQview/X :)
Besides being a lot of fun to read, the latter (which incidentally got some attention on here just a month ago - https://news.ycombinator.com/item?id=29396561) is a whole DOS-native X server. IIUC only Netware's commissioned port of XFree86 comes close to that, but that runs on top of Netware's kernel infrastructure so doesn't really count.
Naturally these sorts of situations sadly represent communicative chasms between geeks and management. Case studies in "it wasn't the end of the world" can perhaps be useful. My standard such example is the HP-20b and HP-30b calculators. On the surface they look just like other calculators HP made around the same time period (2008), but there happen to be a set of pins inside the battery compart
Read the rest
ment that allow reprogramming the non-bootloader-locked microcontroller inside. An SDK (https://www.hpmuseum.org/cgi-sys/cgiwrap/hpmuseum/archv018.c...) (consisting mostly of a keypad test demo) filled in the remaining pieces (how the keyboard matrix worked, and how to get code running on the ARM CPU, basically), and the result was the WP-34S firmware that reimplemented calculator functionality completely from scratch (the code samples in the SDK provided zero such functionality).
TL;DR, this kind of thing can definitely work and be constrained to a nice little obscure niche of very happy people with low/zero external side effects.
In this case, I wouldn't even mind if the code was released under a similar license to what D used to use (https://archive.ph/20161022202138/https://github.com/dlang/d...) before Symantec relinquished control of the project (https://forum.dlang.org/thread/oc8acc$1ei9$1@digitalmars.com) and it was made fully open-source (https://news.ycombinator.com/item?id=14060846). Microsoft licensing GW-BASIC (https://github.com/microsoft/GW-BASIC) and early versions of MS-DOS (https://github.com/microsoft/MS-DOS) under MIT is... fascinating but understandable, yet entirely unnecessary. "View only with no repercussions but not open source" works for historical interest just fine too.
What is a very good question is whether adequate precedent was set by relinquishing D that it would be tractably viable for say one or two individual campaigners to internally achieve something similar for arbitrary effectively-abandonware software that is only of historical interest.
(If this turns out to not be possible because QEMM and/or DESQview are actively being supported in some way I think the whole retrocomputing scene would be very curious to hear about that through the grapevine!)
Thanks for the interesting info about PC-DOS. That's very cool!