April 07, 2005
On writing a simple function that will expand command line wildcards (using std.recls, once I figure that out), I have come accross a situation where the list of command line arguments  char[][] args as defined in main() must change:


void expand_Wildcard( char[][] args )
{
	char[][] tArgs = args.dup;
	int found = 0;

	foreach(int i, char[] file; args )
	{
		...

		args.length = 2; 	// Error vs. foreach
	}		
	etc
}


In the foreach loop I would check every args / "file" and check it for a wildcard. Now should "file" actually contain a *, the args.length would need change.

To make this work, I would need to make a duplicate (not a reference) via:

	char[][] tArgs = args.dup;

Question is, is this correct?

IIRC tArgs would actually be a "reference" to args, meaning, should I change anything in tArgs, this would also change args?

AEon
April 07, 2005
> To make this work, I would need to make a duplicate (not a reference) via:
>
> char[][] tArgs = args.dup;
>
> Question is, is this correct?
>
> IIRC tArgs would actually be a "reference" to args, meaning, should I change anything in tArgs, this would also change args?
>
> AEon

Even with the .dup you are still changing the array inside of the foreach. I
suggest building up the expanded array inside the foreach over args:
 void expand_Wildcard( char[][] args ) {
    char[][] expandedArgs;
    int found = 0;
    foreach(char[] file; args ) {
      if (needsExpansion(file)) {
        char[][] expandedArg = expand(file);
        expandedArgs ~= expandedArg;
      } else {
        expandedArgs ~= file;
      }
   }
 }


Top | Discussion index | About this forum | D home