lenintcapint}//growslice handles slice growth during append.//It is passed the slice element type, the old slice, and the desired new minimum capacity,//and it returns a new slice with at least that capacity, with the old data//copied into it.//The new slice's length is set to the...
TypeOf(slice).Elem() != reflect.TypeOf(value) { return nil, errors.New("param is invalid") } dst := reflect.MakeSlice(reflect.TypeOf(slice), 0, 0) // add the element to the end of slice if index == v.Len() { dst = reflect.AppendSlice(dst, v.Slice(0, v.Len())) dst ...
func TestSliceFn(t *testing.T) { // 参数为引用类型slice:外层slice的len/cap不会改变,指向的底层数组会改变 s := []int{1, 1, 1} newS := sliceAppend(s) // 函数内发生了扩容 t.Log(s, len(s), cap(s)) // [1 1 1] 3 3 t.Log(newS, len(newS), cap(newS)) // [1 1 1 1...
i :=2// Remove the element at index i from a.a[i] = a[len(a)-1]// Copy last element to index i.a[len(a)-1] =""// Erase last element (write zero value).a = a[:len(a)-1]// Truncate slice.fmt.Println(a)// [A B E D] The code copies a single element and runs ...
本文基于golang 1.10版本分析。 slice 结构 slice实际就是一个struct,在runtime/slice.go中的定义如下: 由定义可以看出slice底层...
elements being added// et = element type/// return values:/// newPtr = pointer to the new backing store// newLen = same value as the argument// newCap = capacity of the new backing store/// Requires that uint(newLen) > uint(oldCap).// Assumes the original slice length is...
// fromlen is a known good length providing and equal or greater than tolen, // thereby making tolen a good slice length too as from and to slices have the // same element width. // fromlen是已知的良好长度提供并且等于或大于tolen,从而使得tolen也是良好的切片长度,因为from和to切片具有相同...
golang 的引用类型包括 slice、map、channel、function、pointer 等. 它们在进行赋值时拷贝的是指针值,但拷贝后指针指向的地址是相同的. 本文将简析 slice、map、channel 这三个引用类型. 从它们的底层实现上,探究在进行参数传递时的变量拷贝情况. golang 的切片 slice ...
数组是指一系列同一类型数据的集合。数组中包含的每个数据被称为数组元素(element),这种类型可以是任意的原始类型,比如 int、string 等,也可以是用户自定义的类型。一个数组包含的元素个数被称为数组的长度。在 Golang 中数组是一个长度固定的数据类型,数组的长度是类型的一部分,也就是说 [5]int 和 [10]int ...
// oldCap = original slice's capacity. // num = number of elements being added // et = element type // // return values: // // newPtr = pointer to the new backing store // newLen = same value as the argument // newCap = capacity of the new backing store ...