37 lines
871 B
Go
37 lines
871 B
Go
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package main
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import "fmt"
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// Maps are Go’s built-in associative data type
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func main() {
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// create an empty map, use the builtin: make(map[key-type]val-type).
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m := make(map[string]int)
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// set key/value pairs using typical name[key]=val syntax
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m["k1"] = 7
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m["k2"] = 13
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// printing a map will show all of its key/value pairs
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fmt.Println("map:", m)
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// get a value for a key with name[key]
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v1 := m["k1"]
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fmt.Println("v1: ", v1)
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// len returns the number of key/value pairs
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fmt.Println("len:", len(m))
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// delete removes key/value pairs
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delete(m, "k2")
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fmt.Println("map:", m)
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// optional second return value when getting a value from a map indicates if the key was present in the map
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_, prs := m["k2"]
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fmt.Println("prs:", prs)
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// declare and initialize a new map in the same line
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n := map[string]int{"foo": 1, "bar": 2}
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fmt.Println("map:", n)
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}
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