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| _Types and Values_ | |
| # Disjunctions | |
| Disjunctions, or sum types, define a new type that is one of several things. | |
| In the example, `conn` defines a `protocol` field that must be one of two | |
| values: `"tcp"` or `"upd"`. | |
| It is an error for a concrete `conn` | |
| to define anything else than these two values. | |
| <!-- CUE editor --> | |
| ``` | |
| conn: { | |
| address: string | |
| port: int | |
| protocol: "tcp" | "udp" | |
| } | |
| lossy: { | |
| address: "1.2.3.4" | |
| port: 8888 | |
| protocol: "udp" | |
| } | |
| ``` |