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Returns the value corresponding to the given, or null if such a key is not present in the map. The reason for this is the contract of the Map interface, which says: Instead, it provides a default value for unknown keys, which can be really helpful for grouping and counting algorithms like the following one: from collections import defaultdictĭata =

The defaultdict can also be used with other types and makes sure that you don't get a KeyError when running your code. You can find the Python defaultdict documentation and some examples here but the basic use case is shown in the following snippet: from collections import defaultdict

Kotlin also comes with a similar tool which I want to demonstrate in this little article. Have you ever used a default map or default dict before? If you know Python a bit, you probably saw its defaultdict in action at some point. You also know way to iterate over a HashMap, filter or transform a HashMap.By s1m0nw1 1 Comment Does Kotlin have a default Map? Now you can create, initialize a HashMap, add, update and remove items from a HashMap. In this Kotlin tutorial, we’ve learned some important points of HashMap. The example show you way to initialize a HashMap using hashMapOf() function: var bzkMap: HashMap = hashMapOf("zero" to 0, "onek" to 1000, "twok" to 2000, "bezkoder" to 9999) If you want to create a new HashMap that allows null values and null keys, just use the question mark ? right after the types. We can create a new HashMap using constructor.