Re: how to do this meta-programming? print the address of random element's address of a variable length of arrays?
On Saturday, 12 September 2020 at 03:11:09 UTC, Ali Çehreli wrote:
On 9/11/20 6:44 PM, mw wrote:> e.g.
>
> int[] a = new int[la];
> int[] b = new int[lb];
> int[] c = new int[lc];
> int[] d = new int[ld];
>
>
> the func I want to write, e.g. for 2 arrays (instantiation)
is like this:
>
> void print_random_elem_addr(int[] x, int[] y) {
>auto i = random_int_between(0, x.length);
>auto j = random_int_between(0, y.length);
>print(&(x[i], &(y[j])); // only single print() func call
allowed!
> }
>
>
> But I want one generic function, which can be called as:
>
> print_random_elem_addr(a, b);
> print_random_elem_addr(a, b, c);
> print_random_elem_addr(a, b, c, d);
Thanks for the reply.
If they are all of same type like int[] in this case, then you
but, this is not the intention, we should suppose the array's are
heterogeneous type ...
can variable number of parameters, which means "any number of
int[] arrays" below, elements of which can be called either as
separate arguments or as a single array argument:
import std.stdio;
import std.random;
void print_random_elem_addr(int[][] arrays...) {
... to prevent passing in parameters as array of array like this.
foreach (i, array; arrays) {
const chosen = uniform(0, array.length);
writefln!"Array %s, element %s: %s"(i, chosen,
[chosen]);
actually this writefln will be called n times.
I intentionally require:
print(&(x[i], &(y[j])); // only single print() func call
allowed!
I.e. I want to learn the generic meta-programming way to assemble
such parameter list (&(x[i], &(y[j])) at compile time, it is
possible?
Re: how to do this meta-programming? print the address of random element's address of a variable length of arrays?
On 9/11/20 6:44 PM, mw wrote:> e.g.
>
> int[] a = new int[la];
> int[] b = new int[lb];
> int[] c = new int[lc];
> int[] d = new int[ld];
>
>
> the func I want to write, e.g. for 2 arrays (instantiation) is like this:
>
> void print_random_elem_addr(int[] x, int[] y) {
>auto i = random_int_between(0, x.length);
>auto j = random_int_between(0, y.length);
>print(&(x[i], &(y[j])); // only single print() func call allowed!
> }
>
>
> But I want one generic function, which can be called as:
>
> print_random_elem_addr(a, b);
> print_random_elem_addr(a, b, c);
> print_random_elem_addr(a, b, c, d);
If they are all of same type like int[] in this case, then you can
variable number of parameters, which means "any number of int[] arrays"
below, elements of which can be called either as separate arguments or
as a single array argument:
import std.stdio;
import std.random;
void print_random_elem_addr(int[][] arrays...) {
foreach (i, array; arrays) {
const chosen = uniform(0, array.length);
writefln!"Array %s, element %s: %s"(i, chosen, [chosen]);
}
}
void main() {
auto randomLengthArray() {
return new int[uniform(1, 101)];
}
auto a = randomLengthArray();
auto b = randomLengthArray();
auto c = randomLengthArray();
writeln("As independent arguments:");
print_random_elem_addr(a, b, c);
writeln("As a single argument:");
print_random_elem_addr([a, b, c]);
}
Warning: The array that is automatically generated by the first
print_random_elem_addr() call in main() is short-lived: You cannot store
a slice of it because the array that contains the arguments may be
destroyed upon leaving the function (e.g. in the "independent" case above).
Here is some more information:
http://ddili.org/ders/d.en/parameter_flexibility.html#ix_parameter_flexibility.variadic%20function
There are other ways of doing the same thing. For example, if you want
to work with different ranges, you can use tuple template parameters:
http://ddili.org/ders/d.en/templates_more.html#ix_templates_more.tuple%20template%20parameter
Ali
how to do this meta-programming? print the address of random element's address of a variable length of arrays?
e.g.
int[] a = new int[la];
int[] b = new int[lb];
int[] c = new int[lc];
int[] d = new int[ld];
the func I want to write, e.g. for 2 arrays (instantiation) is
like this:
void print_random_elem_addr(int[] x, int[] y) {
auto i = random_int_between(0, x.length);
auto j = random_int_between(0, y.length);
print(&(x[i], &(y[j])); // only single print() func call
allowed!
}
But I want one generic function, which can be called as:
print_random_elem_addr(a, b);
print_random_elem_addr(a, b, c);
print_random_elem_addr(a, b, c, d);
...
My main question is how to meta-program (generate the parameter
list) this line:
print(&(x[i], &(y[j])); // only single print() func call
allowed!
Thanks!
Re: Vibe-D File Question
On 9/11/20 7:28 AM, Daniel Kozak wrote:
void fun(HTTPServerRequest req, HTTPServerResponse res) nothrow
{
try
{
res.headers["Content-Disposition"] = "filename=\"muj.csv\"";
res.writeBody("some;csv;data", "text/csv");
}
catch (Exception e)
{}
}
Selim, note the Content-Disposition header in particular.
https://developer.mozilla.org/en-US/docs/Web/HTTP/Headers/Content-Disposition
Re: Vibe-D File Question
On Fri, Sep 11, 2020 at 1:15 PM Daniel Kozak wrote:
> On Fri, Sep 11, 2020 at 1:10 PM Selim Ozel via Digitalmars-d-learn <
> digitalmars-d-learn@puremagic.com> wrote:
>
>> It seems like rejected-software forum is flooded with spam, so I
>> decided to ask it here. Is there a way to generate a file -csv
>> for example- on the back-end and serve it to the front-end as a
>> file.
>>
>> Serve static file [1] function does this for files saved on the
>> disk. I want to be able to generate a file during runtime and
>> serve it to the client. Is this possible?
>>
>> Thanks,
>> S
>>
>>
>> [1] https://vibed.org/api/vibe.http.fileserver/serveStaticFile
>>
>>
>>
> https://vibed.org/api/vibe.http.server/HTTPServerResponse.writeBody
>
import vibe.core.core;
import vibe.http.server;
void main()
{
runWorkerTaskDist();
runApplication();
}
void wrap()
{
auto settings = new HTTPServerSettings(":8080");
settings.options |= HTTPServerOption.reusePort;
listenHTTP(settings, );
}
void fun(HTTPServerRequest req, HTTPServerResponse res) nothrow
{
try
{
res.headers["Content-Disposition"] = "filename=\"muj.csv\"";
res.writeBody("some;csv;data", "text/csv");
}
catch (Exception e)
{}
}
Re: Vibe-D File Question
On Fri, Sep 11, 2020 at 1:10 PM Selim Ozel via Digitalmars-d-learn < digitalmars-d-learn@puremagic.com> wrote: > It seems like rejected-software forum is flooded with spam, so I > decided to ask it here. Is there a way to generate a file -csv > for example- on the back-end and serve it to the front-end as a > file. > > Serve static file [1] function does this for files saved on the > disk. I want to be able to generate a file during runtime and > serve it to the client. Is this possible? > > Thanks, > S > > > [1] https://vibed.org/api/vibe.http.fileserver/serveStaticFile > > > https://vibed.org/api/vibe.http.server/HTTPServerResponse.writeBody
Vibe-D File Question
It seems like rejected-software forum is flooded with spam, so I decided to ask it here. Is there a way to generate a file -csv for example- on the back-end and serve it to the front-end as a file. Serve static file [1] function does this for files saved on the disk. I want to be able to generate a file during runtime and serve it to the client. Is this possible? Thanks, S [1] https://vibed.org/api/vibe.http.fileserver/serveStaticFile
