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Paul
Asked: 2020-05-19 20:23:32 +0800 CST 2020-05-19 20:23:32 +0800 CST

How to create a set in Go?

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Like the question, How to create a set in Go?

For example in Python I can do set()or {}to create one that can hold any object. As far as I know there is no equivalent of a set in Go, but you have to use a map.

Is there an equivalent in Go that can hold multiple types? As I would do it?

Thank you!

go

2 Answers

  1. Best Answer

    As you say, go itself doesn't have such a collection type in its standard library, but you can create your own types based on native structures such as arrays, slices or maps.

    Now I think there's no need to reinvent the wheel so you could just use a bookstore that already has all those structures.

    https://github.com/Workiva/go-datastructures

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  2. Go doesn't have an implementation of a set as such within the standard package library, but...

    In go there are interfaces https://tour.golang.org/methods/9 . They are useful for scenarios where you have functions or methods that must take arguments of multiple types. With this in mind it is possible to make a map that stores an interface (if you are looking for a set it is possible to use a map as such); for example here is a data mapping in JSON format:

    m := map[string]interface{} {"name":"nombre", 
"value":53, "data" : map[string]interface{}{"1":true, "2":2}}

    Therefore, using a string or the data type that you deem convenient as a key, it is possible to map various types of data within the interface, be they string, int, map[string]interface{}, bool and even functions . To access these values, just use the corresponding key:

    fmt.Printf("%s\n", m["name"])
fmt.Printf("%d\n", m["value"])
fmt.Printf("%+v\n", m["data"])
fmt.Printf("%t\n", m["data"].(map[string]interface{})["1"])

    Now if this is not enough for what you need, you can always use an available implementation like the one mentioned above https://github.com/Workiva/go-datastructures or implement your own data structure package (why not) .

    Cheers!

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