WoWInterface - What is point of empty brackets?

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- - What is point of empty brackets? (https://www.wowinterface.com/forums/showthread.php?t=58049)

What is point of empty brackets?

Like here. Will this maro behave differently if I just remove those?

The brackets are "or" ... if the first OR the second OR the third is true cast the spell.
Empty bracket (no requirements to be met for being 'true') makes sure the spell is cast when the first two brackets fail.

Totally agree with the previous post; just providing examples with and without the square brackets:

/cast [modifier:SELFCAST, @player] [@mouseover] [ ] Greater Heal

Code:

if my selfcast modifier key is pressed then

    cast Greater Heal on myself

elseif my mouse is over a unit then

    cast Greater Heal on the moused-over unit

else

    cast Greater Heal

end

/cast [modifier:SELFCAST, @player] [@mouseover] Greater Heal

Code:

if my selfcast modifier key is pressed then

    cast Greater Heal on myself

elseif my mouse is over a unit then

    cast Greater Heal on the moused-over unit

end

So adding the empty square brackets provides a "fallback" to still cast a spell even if you didn't have a modifier key pressed nor a mouseover target.