Re: [Vala] Extension Methods

[Uwe Strempel <u strempel googlemail com>]

Hi,
yes you are right.
C# 3.0 syntac for inner-type declaration is not the best.

This syntax:
        public int string.count_words() {
                return this.split_set(" .?").length;
        }
might be better.
Thanks,
regards 
Uwe

2009/3/6 Didier Ptitjes <ptitjes free fr>

Hello Uwe,

Uwe Strempel wrote:

Hi,
is there any feature like extension methods from c# 3.0 in vala supported.
It would be a cool feature in vala and could allow to write better code.

This mechanism is stolen from aspect oriented programming. This is called inner-type declarations.

namespace ExtensionMethods
{
   public static class MyExtensions
   {
       public static int WordCount(this String str)

       {
           return str.Split(new char[] { ' ', '.', '?' }, StringSplitOptions.RemoveEmptyEntries).Length;

       }
   }   }

This would technically be possible. (And would be pretty cool to have as lots of glib libraries provide functions for types defined in other libraries) However I doubt this is in the 1.0 feature plan.

Also that above syntax is ugly. Having static keywords all the way hides the fact this becomes an instance method. I would rather see a syntax closer to the one of aspectJ :

       public int string.count_words() {
               return this.split_set(" .?").length;
       }

thanks,
regards
uwe

Best reagards, Didier.