go / beginner
Snippet
Maps: Go's Key-Value Collections
Maps are Go's built-in hash table implementation for storing key-value pairs. They grow dynamically and accessing a non-existent key returns the zero value of the value type. The comma-ok idiom lets you distinguish between a missing key and an actual zero value.
snippet.go
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package mainimport "fmt"func main() {scores := map[string]int{"Alice": 95,"Bob": 87,}scores["Charlie"] = 92fmt.Println("Bob's score:", scores["Bob"])value, exists := scores["David"]fmt.Printf("David: %d, exists: %t\n", value, exists)delete(scores, "Bob")fmt.Println("Scores:", scores)}
Breakdown
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scores := map[string]int{
Declares map with string keys and int values
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"Alice": 95,
Key-value pair added during initialization
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scores["Charlie"] = 92
Adds new key-value pair to existing map
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value, exists := scores["David"]
Two-value access: first is value, second is boolean existence flag
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delete(scores, "Bob")
Built-in function removes key and its value from map