The objects held in collections can be collections themselves. For example, in this snippet, we have a Map whose values are List objects.

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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
Accessing Elements via [] Combining Collections filter() for Loop forEach() forEach() is a Function Lists map() map() Type Conversions Mutable Lists
Accessing Elements via [] Combining Collections for Loop forEach() forEach() is a Function Maps
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