The lambda expression is optional with first(). first() has a default parameter that is a lambda expression that just returns true. As a result:

  • first() without a lambda expression returns the first item in the list

  • first() with a lambda expression returns the first item in the list for which the lambda expression evaluates to true

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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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