Example Of how decide on the data type

Go-1.18-TypeArgument.go

package main

import (
	"fmt"
	"reflect"
)

// Subtractable is a type constraint that defines subtractable datatypes to be used in generic functions
type Subtractable interface {
	int | int32 | int64 | float32 | float64 | uint | uint32 | uint64
}

// We define the Type parameter V, which is has a Constraint of Subtratacble
// We also say that function parameter a and b has the data type of V
// We then make the function return V
func Subtract[V Subtractable](a, b V) V {
	return a - b
}

func main() {
	result := Subtract(10,20)
	// will Print int
	fmt.Println(reflect.TypeOf(result))
	
	result2 := Subtract[float32](10,20)
	// will Print Float32
	fmt.Println(reflect.TypeOf(result2))
}