• pineapple (16/16) Jan 20 2016 I'd like to make a constructor which takes a variable list of
• =?UTF-8?Q?Ali_=c3=87ehreli?= (32/48) Jan 20 2016 import std.stdio;
• pineapple (5/8) Jan 20 2016 Thank you!
• Daniel Kozak (15/27) Jan 20 2016 struct S
• Daniel Kozak (3/33) Jan 20 2016 isNumeric!(Args[index] should be:
• Daniel Kozak via Digitalmars-d-learn (18/37) Jan 20 2016 V Wed, 20 Jan 2016 12:38:20 +0000
• Daniel Kozak (2/22) Jan 20 2016 Type should be named Index :)

pineapple <meapineapple gmail.com> writes:

I'd like to make a constructor which takes a variable list of 
arguments, of a short list of possible types, with different 
handling depending on the type. I haven't been able to find any 
documentation or examples that did quite what I'm trying to. Help?

A fun pseudocode example of what I'm trying to do:

this(...){
     foreach(argument){
         if(argument is a number){
             do stuff with it;
         }else if(argument is of type A){
             do other stuff;
         }else if(argument is of type B){
             yet more stuff;
         }
     }
}

=?UTF-8?Q?Ali_=c3=87ehreli?= <acehreli yahoo.com> writes:

On 01/20/2016 04:38 AM, pineapple wrote:
 I'd like to make a constructor which takes a variable list of arguments,
 of a short list of possible types, with different handling depending on
 the type. I haven't been able to find any documentation or examples that
 did quite what I'm trying to. Help?

 A fun pseudocode example of what I'm trying to do:

 this(...){
      foreach(argument){
          if(argument is a number){
              do stuff with it;
          }else if(argument is of type A){
              do other stuff;
          }else if(argument is of type B){
              yet more stuff;
          }
      }
 }

import std.stdio;

struct A {
     double d;
}

struct B {
     string s;
}

struct C {
     this(T...)(T args) {
         foreach (arg; args) {
             static if (is (typeof(arg) == int)) {
                 writefln("int: %s", arg);

             } else static if (is (typeof(arg) == A) ) {
                 writefln("A: %s", arg);

             } else static if (is (typeof(arg) == B)) {
                 writefln("B: %s", arg);
             }
         }
     }
}

void main() {
     auto c = C(42, A(1.5), B("hello"));
}

Prints:

int: 42
A: A(1.5)
B: B("hello")

And there is another example here:

 
http://ddili.org/ders/d.en/templates_more.html#ix_templates_more.tuple%20template%20parameter

Ali

pineapple <meapineapple gmail.com> writes:

On Wednesday, 20 January 2016 at 12:56:51 UTC, Ali Çehreli wrote:
 And there is another example here:


 http://ddili.org/ders/d.en/templates_more.html#ix_templates_more.tuple%20template%20parameter

 Ali

Thank you!

What's the purpose of "is" in the type checks?

Also, how would I utilize isNumeric from std.traits here, in 
place of checking only for ints?

Daniel Kozak <kozzi11 gmail.com> writes:

On Wednesday, 20 January 2016 at 13:06:14 UTC, pineapple wrote:
 On Wednesday, 20 January 2016 at 12:56:51 UTC, Ali Çehreli 
 wrote:
 And there is another example here:


 http://ddili.org/ders/d.en/templates_more.html#ix_templates_more.tuple%20template%20parameter

 Ali

 Thank you!

 What's the purpose of "is" in the type checks?

is is use for compare types

 Also, how would I utilize isNumeric from std.traits here, in 
 place of checking only for ints?


struct S
  {
      this(Args...)(Args args)
      {
          foreach(Index, Value;args)
          {
              if (isNumeric!(Args[index]))
              {
                  ...
              }
          }
      }
  }

Daniel Kozak <kozzi11 gmail.com> writes:

On Wednesday, 20 January 2016 at 13:09:13 UTC, Daniel Kozak wrote:
 On Wednesday, 20 January 2016 at 13:06:14 UTC, pineapple wrote:
 On Wednesday, 20 January 2016 at 12:56:51 UTC, Ali Çehreli 
 wrote:
 And there is another example here:


 http://ddili.org/ders/d.en/templates_more.html#ix_templates_more.tuple%20template%20parameter

 Ali

 Thank you!

 What's the purpose of "is" in the type checks?

 is is use for compare types

 Also, how would I utilize isNumeric from std.traits here, in 
 place of checking only for ints?


 struct S
  {
      this(Args...)(Args args)
      {
          foreach(Index, Value;args)
          {
              if (isNumeric!(Args[index]))
              {
                  ...
              }
          }
      }
  }

isNumeric!(Args[index] should be:
isNumeric!(Args[Index]

Daniel Kozak via Digitalmars-d-learn <digitalmars-d-learn puremagic.com> writes:

V Wed, 20 Jan 2016 12:38:20 +0000
pineapple via Digitalmars-d-learn <digitalmars-d-learn puremagic.com>
napsáno:

 I'd like to make a constructor which takes a variable list of 
 arguments, of a short list of possible types, with different 
 handling depending on the type. I haven't been able to find any 
 documentation or examples that did quite what I'm trying to. Help?
 
 A fun pseudocode example of what I'm trying to do:
 
 this(...){
      foreach(argument){
          if(argument is a number){
              do stuff with it;
          }else if(argument is of type A){
              do other stuff;
          }else if(argument is of type B){
              yet more stuff;
          }
      }
 }
 

import std.stdio;

struct S
{
    this(Args...)(Args args)
    {
        foreach(Type, Value;args)
        {
            writefln("Type: %s value: %s", Args[Type].stringof, Value);
        }
    }
}

void main()
{
    auto s = S(1, "string");
}

Daniel Kozak <kozzi11 gmail.com> writes:

On Wednesday, 20 January 2016 at 13:04:23 UTC, Daniel Kozak wrote:
 V Wed, 20 Jan 2016 12:38:20 +0000
 pineapple via Digitalmars-d-learn 
 <digitalmars-d-learn puremagic.com>
 napsáno:


 import std.stdio;

 struct S
 {
     this(Args...)(Args args)
     {
         foreach(Type, Value;args)
         {
             writefln("Type: %s value: %s", Args[Type].stringof, 
 Value);
         }
     }
 }

 void main()
 {
     auto s = S(1, "string");
 }

Type should be named Index :)