Using "list.UniqueItems" as a field validator | CUE

Jonathan Matthews

commented cue

This Commented CUE demonstrates how to use the built-in function list.UniqueItems to ensure that a list’s items are unique.

package example

import "list"

aList: list.UniqueItems
aList: [1, 2.0, 3, "four", 5, 5.0, false,
	{a: 1, b: "2", c: false}, // validation error
	{a: 1, b: "2", c: true},
	{a: 1, b: 2, c: false},
	{a: 1, b: "2", c: false}, // validation error
]

$ cue vet
aList: invalid value [1,2.0,3,"four",5,5.0,false,{a:1,b:"2",c:false},{a:1,b:"2",c:true},{a:1,b:2,c:false},{a:1,b:"2",c:false}] (does not satisfy list.UniqueItems):
    ./file.cue:5:8
    ./file.cue:6:8

Issue #49 tracks the documentation of precisely what CUE means by values being “equivalent”, “equal”, or “comparable”. When this documentation is complete it will be linked to from this guide.

The list built-in package

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