void logMsg(string file, string msg)
{
  //Log the message to the file.
}

struct Log
{
   string logFile;
   LogInfo toLog;
}

class Foo
{
  void bar() { /* do something */ }
  @Log("fooInfo.txt", LogInfo.methodCall | LogInfo.returnValue)
void baz()
  {
    //Doess
  }
}

Sry accedentaly clicked send while writing..

Is it possible to inject code into a method with UDA's?
For example if i wanted a method to do some logging when it's
called.

Something like the following.

void logMsg(string file, string msg)
{
  //Log the message to the file.
}

struct Log
{
   string logFile;
}

class Foo
{
  void bar() { /* do something */ }
  @Log("fooInfo.txt")
  int baz()
  {
    //Does some calculation and returns some value.
  }
}


would expand the class Foo to (at compile time)

class Foo
{
	void bar() { } //unchanged
	int baz()
	{
	   logMsg("fooInfo.txt", "Method Foo.baz was called.");

	   //Let baz do it's thing
	}
}

I know that this can be done by using a wrapper template that creates
a subclass but it would be nice if the code could just be injected
with the UDA's somehow.

On 2013-10-20 01:16, TheFlyingFiddle wrote:
> Is it possible to inject code into a method with UDA's?
> For example if i wanted a method to do some logging when it's
> called.

It's only possible to inject code using a template or string mixin.

-- 
/Jacob Carlborg

> It's only possible to inject code using a template or string mixin.

Ah, too bad. Thanks for the answer.

On Sunday, 20 October 2013 at 11:58:41 UTC, TheFlyingFiddle wrote:
>> It's only possible to inject code using a template or string mixin.
>
> Ah, too bad. Thanks for the answer.

Well, it is possible to do it if you use some kind of own framework for declarative stuff and call the function only from it (thus implementing check of attached UDA's inside of the framework). Actual function modification is not possible.