Can I output strings using core.stdc.stdio?
Godnyx
rempas at tutanota.com
Wed Dec 23 12:23:17 UTC 2020
On Wednesday, 23 December 2020 at 09:50:03 UTC, Ali Çehreli wrote:
> On 12/23/20 1:06 AM, Godnyx wrote:
>
> > for (ulong i = 0; i < args.length; i++) {
> > if (typeof(args[i]).stringof == "string")
> > printf("%s\n", args[i].toStringz);
> > }
>
> I replaced for with foreach and it worked (and I passed
> "prompt"). static foreach would work as well.
>
> import core.stdc.stdio : printf;
> import std.string : toStringz;
>
> void put(A...)(string prompt, A args) {
> foreach (arg; args) {
> if (typeof(arg).stringof == "string")
> printf("%s\n", arg.toStringz);
> }
> }
>
> void main() {
> string h = "World!";
> string w = "World!";
> put("prompt", h, w);
> }
>
> But it can get better: you don't want to compare typeof with
> "string" at run time. Instead, there shouldn't be any code
> generated for the non-string cases. Enter 'static if' and the
> 'is' expression to feel better. :)
>
> import core.stdc.stdio : printf;
> import std.string : toStringz;
>
> void put(A...)(string prompt, A args) {
> static foreach (arg; args) {
> static if (is (typeof(arg) == string)) {
> printf("%s\n", arg.toStringz);
> }
> }
> }
>
> void main() {
> string h = "World!";
> string w = "World!";
> put("prompt", h, w);
> }
>
> Ali
Probably the best solution! It also let's me use types other than
string! Example: put("Prompt:", "Hello, my age is: ", 19, true);
tho still I can't print anything. This is the code:
void put(A...)(string prompt, A args) {
static foreach (ulong i; 0..args.length) {
static if (is(typeof(arg) == string))
printf("%s\n", args[i].toStringz);
static if (is(typeof(arg) == int))
printf("%i\n", args[i]);
static if (is(typeof(arg) == bool)) {
if (arg)
printf("true");
else
printf("false");
}
}
}
void main() {
put("Prompt:", "Hello, my age is: ", 19, true);
}
Any ideas?
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