你不知道的Go

1.匿名结构

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var person struct {
    name      string
    age int
}
person.name="jack"

声明时初始化：

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st := struct {
	name string
	age  int
}{
	"Jack",
	12,
}
fmt.Println(st.name)

2.抢占式调度器

In prior releases, a goroutine that was looping forever could starve out other goroutines on the same thread, a serious problem when GOMAXPROCS provided only one user thread. In Go 1.2, this is partially addressed: The scheduler is invoked occasionally upon entry to a function. This means that any loop that includes a (non-inlined) function call can be pre-empted, allowing other goroutines to run on the same thread.

从golang1.2起，携程调度器为抢占式的，但抢占发生在每次进入函数前，所以，如果循环内的函数被编译器优化成了inline function，那么自然不会发生调度。

3.清空slice

清空slice并保留内存空间

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a := []string{"A", "B", "C", "D", "E"}
a = a[:0]
fmt.Println(a, len(a), cap(a)) // [] 0 5
fmt.Println(a[:2])  // [A,B]
go
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