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| # Null Coalescing |
| |
| With null coalescing we really mean error, or bottom, coalescing. |
| The defaults mechanism for disjunctions can also be |
| used to provide fallback values in case an expression evaluates to bottom. |
| |
| In the example the fallback values are specified |
| for `a` and `b` in case the list index is out of bounds. |
| |
| <!-- CUE editor --> |
| ``` |
| list: [ "Cat", "Mouse", "Dog" ] |
| |
| a: list[0] | "None" |
| b: list[5] | "None" |
| ``` |
| |
| <!-- result --> |
| ``` |
| list: [ "Cat", "Mouse", "Dog" ] |
| |
| a: "Cat" |
| b: "None" |
| ``` |
