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tj
tj

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Generics in Golang πŸš€

Golang just released a beta version, offering a preview or atleast a working example of how to use generics and how it works with the compiler.


package main

import (
    "fmt"
)

func Writer[T string | int](w T) {
    fmt.Println(w)
}
func main() {
    Writer("Hello")
    Writer(1)
}
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as simple as it looks, it's really unique and powerful.
It has both the easy and understandable syntax that go already offers and more.
It works like any other language generics.

Lets assume this piece of code.


package main

import (
    "fmt"
)

func Writer[T string | int](w T) {
    fmt.Println(w)
}
func main() {
    Writer[int]("Hello")
    Writer(1)
}
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This code, as you may have guessed returns an error.

 cannot use "Hello" (untyped string constant) as int value in argument to Writer[int]
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To fix it, either we'd have to change the generic type to "string" or change the param of the function to int type.

package main

import (
    "fmt"
)

func Writer[T string | int](w T) {
    fmt.Println(w)
}
func main() {
    Writer[string]("Hello")
    Writer[int](1) 
}
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Notes

  • Golang hasnt yet announced a stable version, therefore it is not adviced to use it in production.
  • Due to addition of generics go 1.18-beta is roughly 15% slower check out more information about it here

Upgrading Version

Due to go 1.18 being unstable, golang has made the version a seperate executable.
You can download it here
and use

go1.18beta1 
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in the cli to check out the help menu.

OR

Install go1.18beta using the go cli (if you already have it installed)

go install golang.org/dl/go1.18beta1@latest
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and then use

go1.18beta1
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instead of

go
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Fyi, go does not update it just installs a seperate executable for testing out the beta version

Well have fun looking at the new features, until next time 🀠

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