firstOrNull() works nicely with the Elvis operator (?:). You get either the first matching item in the list or whatever the right side of the Elvis operator evaluates to. This functions as a way of getting a default value if the list does not contain a matching item.

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Accessing Elements via [] any() any() and Short Circuits Array Modification Arrays Combining Collections filter() first() first() Sans Lambda firstOrNull() firstOrNull() and the Elvis Operator fold() for Loop forEach() forEach() is a Function joinToString() Lists map() map() Type Conversions Maps Mutable Lists Sets Typed Arrays
any() any() and Short Circuits Chaining Higher-Order Functions first() first() Sans Lambda firstOrNull() firstOrNull() and the Elvis Operator fold() Function Reference Function Reference for Member Functions Function References and Receivers Function Types Function Types and Direct Invocation Function Types and Parameters Functional Interfaces joinToString() Type Aliases
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