My macro for Minecraft in the Keyran program allows you to automatically swap items in slots 1 and 7. It also includes the function of automatic promotion of items in slots 4-10 for 4-10 seconds, depending on the moment when a successful swap is visible. 

This macro can be useful in PvP battles, where you need to quickly change weapons and use certain items to gain an advantage over the enemy. 
For example, when activating a macro by pressing a button, it will automatically place the sword in slot 7, and the masika item in slot 3. Then, if the swap was successful (for example, we saw the swap at the moment when the items were swapped), the macro will automatically start promoting items in slots 4-10 for 4-10 seconds.
Note that with a successful swap, we can quickly deal with the enemy, because the enemy will not be ready to attack or defend, while we are already ready to use the desired item.
For example, with a successful swap with a sword in slot 7, we can inflict serious damage to the enemy and even kill him, leaving him with 1 hp.

Thus, this macro can significantly increase our chances of winning PvP battles and make the gameplay more interesting and dynamic.