#go languageIn map, map is a set of kv pairs. The bottom layer uses a hash table and a linked list to resolve conflicts. Through the compiler and runtime, all map objects share the same code.
Golang’s method of judging whether the key in the map does not exist:
The judgment method is value,ok := map[key], if ok is true, it exists, if ok is false, the key of the map does not exist. .
package main import "fmt" func main() { demo := map[string]bool{ "a": false, } //错误,a存在,但是返回false fmt.Println(demo["a"]) //正确判断方法 _, ok := demo["a"] fmt.Println(ok) }
Output
false true
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