Simple unit group question

[Emu.Man00]

What is the most efficient JASS equivalent of

• Set g = (Units within 400.00 of (Position of (Triggering unit)) matching (((Triggering player) is an enemy of (Owner of (Matching unit))) Equal to True))

Tried to find myself but the main problem was all the functions were asking for a 'boolexpr' argument. I know how to use it, but only as a separate function, and I assume there is a better way to do this?

 

[WolfieeifloW]

private function GroupFilter takes nothing returns boolean
    return (IsUnitEnemy(GetFilterUnit(), GetOwningPlayer(GetTriggerUnit())))
endfunction

private function WHATEVER takes nothing returns nothing
    call GroupEnumUnitsInRange(g, GetUnitX(GetTriggerUnit()), GetUnitY(GetTriggerUnit()), 400, Condition(function GroupFilter))
endfunction

I don't believe you can inline it without getting all units in range then using a FirstOfGroup() loop with an if statement.

 

[Emu.Man00]

Mmmmm, alright. Thanks.