50 lines
1.2 KiB
Go
50 lines
1.2 KiB
Go
// 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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// set is a data structure that contain the same element only once.
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// maps can also be used as sets.
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// let's create a slice of coders.
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coders := []string{"pike", "thompson", "lovelace", "knuth"}
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// let's create a map for tracking whether they are gopher or not.
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gophers := make(map[string]bool, len(coders))
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// let's mark the gophers
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gophers["thompson"] = true
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gophers["pike"] = true
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// print the gophers
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for _, coder := range coders {
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// i see this a lot, especially in beginner code.
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//
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// you don't have to use the "comma, ok" idiom.
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// m[k] = false for non-existing bool elements.
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// use it to your advantage.
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//
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// DONT:
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// if _, ok := gophers[coder]; ok { ... }
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//
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// DO:
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// for this trick to work, you should set all the map elements to true
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if gophers[coder] {
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fmt.Printf("%s is a gopher.\n", coder)
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// don't use else. stay at the same indentation level.
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continue
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}
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fmt.Printf("%s is not a gopher.\n", coder)
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}
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}
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