need help with macros

If you can't already tell, I'm still new to the game. I'm trying to figure out if it is possible to have macro that will do the following: If I have a friendly targeted (tank) it will assist him and perform an action. If I don't have a friendly targeted, the action will work as normal.
So here is my scenario that this would be useful: I'm a DD in a group. While there aren't any adds that need to be taken care of I simply target the tank and fire away. When adds or groups are involved I can either continue assisting the tank by leaving him selected or I can swap over to an enemy if that is what is needed.

I used to use a similar macro when I played WoW and it was great at avoiding aggro (i wasn't always quick enough at swapping and this made it much better)while still allowing me to do all my hunter duties. The one I was using was a bit more complicated than this but this should get the job done. I would really appreciate any help.

Hi,

/micon "Action Name" ------ so you have correct icon with the cooldown+cost+range
/ac "Action Name" <tt> ------- uses action on the target of your target
/ac "Action Name" <t> -------- uses action on your target

http://ffxiv.consolegameswiki.com/wiki/Commands

Names for actions are case sensitive. If it is only one word no need for the quotation marks

Thanks Thaliss! I'm still trying to understand how the macro system works and this will be a good start. Then I can just modify it as I go and get a better understanding of the maceo system. Thanks again.

The problem with that macro is that any tank worth his salt is going to be switching targets a lot. You don't want to follow the tank's targeting around. You want to focus on the first kill target until that's dead, then move on to the next.

I'd suggest setting the tank as your focus (I don't remember the default keybind for this. Ctrl+F, perhaps. The macro command is /focustarget), and then using a macro that's just "/assist <f>" to acquire the tank's target once per enemy.

I'm not sure how smart or stupid /assist is. If it's smart enough to know you can't really assist hostiles, you could use:
/assist <t>
/ac "Something" <t>

But if /assist is stupid, that'll just end up swapping targets back and forth between tank and mob.

Good point Bixby. That macro did work as I requested though. I'm going to spend time tonight to refine it. After thinking about how I had things setup before I remembered that only my opening move had the assist command in it which was tied to my focus target (usually the tank). The rest of my single target macros were just the attack with a line added to make my pet attack the same target.
So what I think I'll do is just have one macro that assists my focus and have the rest just be the regular actions.