env CUE_EXPERIMENT=evalv3=0
! exec cue eval
cmp stderr outv2

env CUE_EXPERIMENT=evalv3
exec cue eval
cmp stdout outv3

-- test.cue --
package foo

// This only works in the new evaluator as of this writing.
y: 1 | {y: 1}
y

-- outv3 --
y: 1
-- outv2 --
2 errors in empty disjunction:
conflicting values 1 and {y:(1|{y:1}),y} (mismatched types int and struct):
    ./test.cue:1:1
    ./test.cue:4:4
cannot add field y: was already used:
    ./test.cue:4:9
