Logically, we know that unifying any field with itself will result in an identical value. Unifying "foo" with "foo" must equal "foo"; unifying the non-concrete value int with int must, similarly, result in int.

CUE takes advantage of this property to resolve cycles between fields by simply ignoring the cycle and then unifying the fields a single time. This achieves the same result as attempting to follow the reference cycle ad infinitum.

labels: {
	app: "foo"
}
selectors: {
	name: "bar"
}

// This cycle can be resolved.
labels:    selectors
selectors: labels

$ cue export file.cue
{
    "labels": {
        "app": "foo",
        "name": "bar"
    },
    "selectors": {
        "name": "bar",
        "app": "foo"
    }
}