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digitalmars.D - [][] to **

reply Lucas Goss <lgoss007 gmail.com> writes:
How can I convert char[][] to char**?

In C I can just do:
int main(int argc, char** argv)
{
	someFunc(args);
	return 0;
}

But I'm drawing a blank for how to do that in D...
int main(char[][] args)
{
	someFunc(???)
	return 0;
}

// someFunc(char** val)
Mar 23 2006
parent reply "Jarrett Billingsley" <kb3ctd2 yahoo.com> writes:
"Lucas Goss" <lgoss007 gmail.com> wrote in message 
news:dvvhdt$2qe3$1 digitaldaemon.com...

 How can I convert char[][] to char**?
 But I'm drawing a blank for how to do that in D...
 int main(char[][] args)
 {
 someFunc(???)
 return 0;
 }

 // someFunc(char** val)



Well, it's can't really be directly done.  In D, you can easily convert a 
char[] to a char*, but since a char[][] is an array of _D_ arrays of 
characters, you wouldn't be able to just cast it to a char**.

Instead, you'll have to do it manually:

import std.stdio;
import std.string;

char** stringsToCharz(char[][] arr)
{
 char** s = new char*[arr.length];
 foreach(uint i, char[] string; arr)
  s[i] = toStringz(string);

 return s;
}

void main()
{
 char[][] strings = new char[][2];
 strings[0] = "hi";
 strings[1] = "bye";

 char** C = stringsToCharz(strings);

 for(uint i = 0; i < strings.length; i++)
  printf("%s\n", C[i]);
}

I'm assuming that the function that you want to pass this char** to is a 
C-style function, and as thus, I've used toStringz() in order to make the 
strings null-terminated.
Mar 23 2006
parent Lucas Goss <lgoss007 gmail.com> writes:
Jarrett Billingsley wrote:

 Well, it's can't really be directly done.  In D, you can easily convert a 
 char[] to a char*, but since a char[][] is an array of _D_ arrays of 
 characters, you wouldn't be able to just cast it to a char**.
 
 Instead, you'll have to do it manually:



Ah. Thanks! :D
Mar 23 2006