• Nub Public (6/6) Jun 26 2011 Is it possible to get the signature of a function and make a delegate
• Robert Clipsham (25/31) Jun 26 2011 ----
• Nub Public (2/6) Jun 26 2011 Thanks. This is exactly what I need.

Nub Public <nubpublic gmail.com> writes:

Is it possible to get the signature of a function and make a delegate 
type from it?


Something like this:

bool fun(int i) {}

alias (signature of fun) DelegateType;

DelegateType _delegate = delegate(int i) { return i == 0; };

Robert Clipsham <robert octarineparrot.com> writes:

On 26/06/2011 08:08, Nub Public wrote:
 Is it possible to get the signature of a function and make a delegate
 type from it?


 Something like this:

 bool fun(int i) {}

 alias (signature of fun) DelegateType;

 DelegateType _delegate = delegate(int i) { return i == 0; };

----
alias typeof(&fun) FuncType;
FuncType _function = function(int i) { return i == 0; };
----

Note that fun() here has no context, so FuncType is an alias for bool 
function(int). If you truely want a delegate type, you could use the 
following:

----
import std.traits;
template DelegateType(alias t)
{
     alias ReturnType!t delegate(ParameterTypeTuple!t) DelegateType;
}
DelegateType!fun _delegate = (int i) { return i == 0; };
----

The other alternative is to just use auto, there's no guarantee it will 
be the same type as the function though:
----
auto _delegate = (int i) { return i == 0; }
----

Hope this helps.

-- 
Robert
http://octarineparrot.com/

Nub Public <nubpublic gmail.com> writes:

On 6/26/2011 5:45 PM, Robert Clipsham wrote:
 template DelegateType(alias t)
 {
      alias ReturnType!t delegate(ParameterTypeTuple!t) DelegateType;
 }


Thanks. This is exactly what I need.