sync a //defines a "sync group"

// any two parts of a sync group can not run at the same time
n = counter()

part1 = ?g
part2 = ?g


-> if n > 10 {
    a[part1] {
        // ... part [1] of sync group a
    }
} else {
    a[part2] {
        // ... part [2] of sync group a
    }
}

if n == 12 {
    // since this could happen at the
    // same time as a[1] (bacause of the ->)
    // this must also be a[1]
    a[part1] {
        // ...
    }
}


// if a sync group has only one part it will be optimized away

// in a situation like this
a[1] {
    b[1] {
        //...
    }
}

a[1] {
    b[2] {
        //...
    }
}

b[3] {
        //...
}

// sync group a can be optimized away


// FURTHER STUFF:


// a synchronous macro is defined like this

m = sync (arguments) {
    // ...
}

// a synchronous macro is assumed to be done when it returns,
// so its triggers can be toggled off
// if it is called with a -> it is not assumed to be sync anymore

// if it should still be sync with a ->,
// the tag #[force_sync] can be applied