慕的地6264312
我会迭代切片索引的向量。单索引迭代器：// Iterator of a slice index. `len` equals to the length of the slicetype IdxIter struct { idx uint len uint}// Returns true is the iteration is over.func (i IdxIter) Done() bool { return i.idx >= i.len}// Builds the next iteration value. If called for the last index,// the next value's `Done` returns `true`.func (i *IdxIter) Next() { i.idx++}// Resets the iteratorfunc (i *IdxIter) Reset() { i.idx = 0}// The index valuefunc (i IdxIter) Idx() uint { return i.idx}索引向量的迭代器：// Index iterator for a slice of slicestype IdxVectorIter []IdxIter// Returns true is the iteration is over.func (ii IdxVectorIter) Done() bool { last := len(ii) - 1 return ii[last].Done()}// Builds the next iteration value. If called for the last index vector,// the next value's `Done` returns `true`.func (ii IdxVectorIter) Next() { if len(ii) == 0 { return } last := len(ii) - 1 for pos := range ii[:last] { ii[pos].Next() if ii[pos].Done() { ii[pos].Reset() } else { return } } ii[last].Next()}这样，切片切片的迭代就很简单了：func main() { words := [][]string{ {"lorem", "ipsum"}, {}, {"Alpha", "Beta", "Gamma"}, {"X", "Y", "Z"}, } // Fixed buffer for the combinations of words dst := make([]string, len(words)) // Iteration loop for ii := NewIdxVectorFromSlices(words); !ii.Done(); ii.Next() { GetTo(words, dst, ii) fmt.Printf("%v\n", dst) }}完整代码https://go.dev/play/p/ecjjcAEexZO输出[lorem Alpha X][ipsum Alpha X][lorem Beta X][ipsum Beta X][lorem Gamma X][ipsum Gamma X][lorem Alpha Y][ipsum Alpha Y][lorem Beta Y][ipsum Beta Y][lorem Gamma Y][ipsum Gamma Y][lorem Alpha Z][ipsum Alpha Z][lorem Beta Z][ipsum Beta Z][lorem Gamma Z][ipsum Gamma Z]