44 lines
1.1 KiB
Go
44 lines
1.1 KiB
Go
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// For more tutorials: https://blog.learngoprogramming.com
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//
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// Copyright © 2018 Inanc Gumus
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// Learn Go Programming Course
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// License: https://creativecommons.org/licenses/by-nc-sa/4.0/
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//
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package main
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import "fmt"
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func main() {
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nums := []int{1, 2, 3}
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// Store a slice in `any`
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var any interface{}
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any = nums
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// `any` is an empty interface value, it's not a slice.
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// You cannot get its length. It has no length.
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// _ = len(any)
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// When you extract the slice from it, you can get the slice's length.
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_ = len(any.([]int))
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// You cannot assign an `[]T` slice to `[]interface{}` slice.
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// Where `T` can be of any type.
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// Reason: `[]interface{}` is a slice, it's not an `empty interface` value.
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var many []interface{}
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// many = nums
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// The same reason that you can't assign an `[]int` to a `[]string`.
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// var words []string = nums
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// You need to copy the elements from `nums` to `many` manually.
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for _, n := range nums {
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many = append(many, n)
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}
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fmt.Println(many)
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// Each element of the `many` slice is an `empty interface` value.
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// el := many[0]
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}
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