Can I output strings using core.stdc.stdio?

[Ali Çehreli]

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