From: bc@freeuk.com
On 24/10/2025 00:04, Keith Thompson wrote:
> bart writes:
>> On 23/10/2025 02:19, Thiago Adams wrote:
>>> Em 22/10/2025 18:39, Keith Thompson escreveu:
>>>> This is cross-posted to comp.lang.c and comp.lang.c++.
>>>> Consider redirecting followups as appropriate.
>>>>
>>>> cdecl, along with c++decl, is a tool that translates C or C++
>>>> declaration syntax into English, and vice versa. For example :
>>>>
>>>> $ cdecl
>>>> Type `help' or `?' for help
>>>> cdecl> explain const char *foo[42]
>>>> declare foo as array 42 of pointer to const char
>>>> cdecl> declare bar as pointer to function (void) returning int
>>>> int (*bar)(void )
>>>>
>>>> It's also available via the web site .
>>> This one does not work:
>>> void (*f(int i))(void)
>>
>> KT said the newer version is only available by building from source
>> code, which must be done under some Linux-compatible system.
>
> As far as I know, it should build on just about any Unix-like system,
> not just ones that happen to use the Linux kernel. Perhaps that's what
> you mean by "Linux-compatible"? If so, I suggest "Unix-like" would be
> clearer. (I'm building it under Cygwin as I write this.)
>
>> I've had a look: it comprises 32Kloc of configure script, and 68Kloc
>> of C sources, so 100Kloc just to decode declarations! (A bit longer
>> than the 2-page version in K&R2.)
>
> Yes, and neither you nor I had to write any of it. I cloned the repo,
> ran one command (my wrapper script for builds like this), and it works.
>
> I wonder how many lines of code are required for the specification of
> the x86_64 CPU in the computer I'm using to write this. But really,
> it doesn't matter to me, since that work has been done, and all I
> have to do is use it.
>
> The configure script is automatically generated (I mentioned the
> "bootstrap" script that generates it if you build from the git repo).
>
> I suppose building it under Windows (without some Unix-like layer
> like MinGW or Cygwin) would be more difficult. That's true of
> a lot of tools that are primarily used on Unix-like systems.
> It's likely that the author of the code doesn't care about Windows.
>
> I agree that it can be a problem that a lot of code developed for
> Unix-like systems is difficult to build on Windows. For a lot
> of users, an emulation layer like Cygwin, MinGW, or WSL is a good
> enough solution. If it isn't for you, perhaps you could help solve
> the problem. Perhaps the GNU autotools could be updated with better
> Windows support. I wouldn't know how to do that; perhaps you would.
>
> "Don't use autotools" is not a good solution, since there are so
> many software packages that depend on it, often maintained by people
> who don't care about Windows.
>
>> (There's a further 30Kloc of what looks like C library code. So is
>> this a complete C compiler, or does it still only do declarations?)
>
> I haven't looked at the source code (I haven't needed to), but the man
> page indicates that this version of cdecl recognizes a number of types
> defined in the standard library, such as FILE, clock_t, and
> std::partial_ordering (remember that it includes C++ support).
>
> I don't know whether all this could be done in fewer lines of code, and
> frankly I don't much care. The tool works and is useful, and I didn't
> have to write it.
>
> Have you tried using it? I'm sure you have some system where you could
> build it.
>
>> Regarding your example, my old C compiler (which is a fraction the
>> size of this new Cdecl) 'explains' it as:
>>
>> 'ref proc(int)ref proc()void'
>>
>> (Not quite English, more Algol68-ish.)
>
> Can I run your old C compiler on my Ubuntu system?
>
The old one needed a tweak to bring it up-to-date for my newer C
transpiler. So it was easier to port the feature to the newer product.
Download https://github.com/sal55/langs/blob/master/ccu.c
(Note: 86Kloc/2MB file; this is poor quality, linear C generated from
intermediate language.)
Build instructions are at the top. Although this targets Win64, it works
enough to demonstrate the feature above. Create this C file (say test.c):
int main(void) {
void (*f(int i))(void);
$showmode f;
}
Run as follows (if built as 'ccu'):
./ccu -s test
It will display the type during compilation.
Obviously this is not a dedicated product (and doing the reverse needs a
separate program), but I only needed to add about 10 lines of code to
support '$showmode'.
Original source, omitting the unneeded output options, would be 2/3 the
size of that configure script.
--- SoupGate-Win32 v1.05
* Origin: you cannot sedate... all the things you hate (1:229/2)
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