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digitalmars.D.learn - Passing a variable number of slices into a function

reply repr-man <jxl.ppg gmail.com> writes:
Is there any way to pass an unknown number of slices into a 
function?  I'm trying to do something along the lines of:

void func(T)(T[] args...)
{
     //...
}

That wasn't working, so I tried using another generic type where 
T was already defined:

void func(U)(U args...)
if(is(U == T[])
{
     //...
}

This didn't work either, so I wanted to know if I was going in 
the right direction or if I was missing something obvious.

Thanks for the help!
Jun 21 2020
parent reply user1234 <user1234 12.de> writes:
On Monday, 22 June 2020 at 01:47:49 UTC, repr-man wrote:

 Is there any way to pass an unknown number of slices into a 
 function?  I'm trying to do something along the lines of:

 void func(T)(T[] args...)
 {
     //...
 }

 That wasn't working,

 [...]

 Thanks for the help!


Can you provide more details for "that wasnt working" ? because

   void func(T)(T[] args...)
   {
     writeln(args.length);
   }

   void main()
   {
     int[] a,b;
     func(a[0..$],b[0..$]);
   }

works, so there must be a missing detail.
Maybe each slice has different type ?
Jun 21 2020
next sibling parent Adam D. Ruppe <destructionator gmail.com> writes:
On Monday, 22 June 2020 at 02:04:06 UTC, user1234 wrote:

 Maybe each slice has different type ?


in some cases T[][]... will work better too. depends on the 
details here....
Jun 21 2020
prev sibling parent Steven Schveighoffer <schveiguy gmail.com> writes:
On 6/21/20 10:04 PM, user1234 wrote:

 On Monday, 22 June 2020 at 01:47:49 UTC, repr-man wrote:

 Is there any way to pass an unknown number of slices into a function?  
 I'm trying to do something along the lines of:

 void func(T)(T[] args...)
 {
     //...
 }

 That wasn't working,

 [...]

 Thanks for the help!


 
 Can you provide more details for "that wasnt working" ? because
 
    void func(T)(T[] args...)
    {
      writeln(args.length);
    }
 
    void main()
    {
      int[] a,b;
      func(a[0..$],b[0..$]);
    }
 
 works, so there must be a missing detail.
 Maybe each slice has different type ?


I think the problem is that typesafe variadics bind to arrays as well as 
individual parameters. So func(a[0 .. $]) for instance would resolve as 
func!int instead of the desired func!(int[]).

The answer might be:

func(T)(T[][] args...)

as Adam says.

-Steve
Jun 22 2020