Golang State.Next方法代码示例

// Copy matching Lua table entries to a struct, given the struct type
// and the index on the Lua stack.
func CopyTableToStruct(L *lua.State, t reflect.Type, idx int) interface{} {
	was_ptr := t.Kind() == reflect.Ptr
	if was_ptr {
		t = t.Elem()
	}
	s := reflect.New(t) // T -> *T
	ref := s.Elem()
	L.PushNil()
	if idx < 0 {
		idx--
	}
	for L.Next(idx) != 0 {
		key := L.ToString(-2)
		f := ref.FieldByName(strings.Title(key))
		if f.IsValid() {
			val := luaToGoValue(L, f.Type(), -1)
			f.Set(val)
		}
		L.Pop(1)
	}
	if was_ptr {
		return s.Interface()
	}
	return s.Elem().Interface()
}

func copyTableToMap(L *lua.State, t reflect.Type, idx int, visited map[uintptr]interface{}) interface{} {
	if t == nil {
		t = tmap
	}
	te, tk := t.Elem(), t.Key()
	m := reflect.MakeMap(t)

	// See copyTableToSlice.
	ptr := L.ToPointer(idx)
	if !luaIsEmpty(L, idx) {
		visited[ptr] = m.Interface()
	}

	L.PushNil()
	if idx < 0 {
		idx--
	}
	for L.Next(idx) != 0 {
		// key at -2, value at -1
		key := reflect.ValueOf(luaToGo(L, tk, -2, visited))
		val := reflect.ValueOf(luaToGo(L, te, -1, visited))
		if val.Interface() == nullv.Interface() {
			val = reflect.Zero(te)
		}
		m.SetMapIndex(key, val)
		L.Pop(1)
	}
	return m.Interface()
}

func popMap(L *lua.State) map[string]interface{} {
	m := make(map[string]interface{})
	L.PushNil()
	for L.Next(-2) != 0 {
		if L.IsString(-2) {
			var v interface{}
			if L.IsBoolean(-1) {
				v = L.ToBoolean(-1)
			} else if L.IsNumber(-1) {
				var t float64
				t = L.ToNumber(-1)
				if t == float64(int64(t)) {
					v = int(t)
				} else {
					v = t
				}
			} else if L.IsString(-1) {
				v = L.ToString(-1)
			} else if L.IsNil(-1) {
				v = nil
			} else if L.IsTable(-1) {
				v = popMap(L)
			}
			m[L.ToString(-2)] = v
		}
		L.Pop(1)
	}
	return m
}

func outputNumbersToStrings(L *lua.State) {
	L.GetGlobal("output")

	if !L.IsTable(-1) {
		L.NewTable()
		L.SetGlobal("output")
	}

	L.GetField(-1, "tags")
	if L.IsTable(-1) {
		// First key.
		L.PushNil()
		for L.Next(-2) != 0 {
			// Use 'key' at index -2 and 'value' at index -1.
			if L.IsString(-2) && L.IsString(-1) {
				// Convert numbers to strings.
				L.ToString(-1)
				L.SetField(-3, L.ToString(-2))
			} else {
				// Remove 'value' and keep 'key' for next iteration.
				L.Pop(1)
			}
		}
	}
	L.Pop(1)

	L.Pop(1)
}

func pairsAux(L *lua.State) int {
	L.CheckType(1, lua.LUA_TTABLE)
	L.SetTop(2) // Create a 2nd argument if there isn't one.
	if L.Next(1) != 0 {
		return 2
	}
	L.PushNil()
	return 1
}

func luaIsEmpty(L *lua.State, idx int) bool {
	L.PushNil()
	if idx < 0 {
		idx--
	}
	if L.Next(idx) != 0 {
		L.Pop(2)
		return false
	}
	return true
}

func copyTableToStruct(L *lua.State, t reflect.Type, idx int, visited map[uintptr]interface{}) interface{} {
	if t == nil {
		RaiseError(L, "type argument must be non-nill")
	}
	wasPtr := t.Kind() == reflect.Ptr
	if wasPtr {
		t = t.Elem()
	}
	s := reflect.New(t) // T -> *T
	ref := s.Elem()

	// See copyTableToSlice.
	ptr := L.ToPointer(idx)
	if !luaIsEmpty(L, idx) {
		if wasPtr {
			visited[ptr] = s.Interface()
		} else {
			visited[ptr] = s.Elem().Interface()
		}
	}

	// Associate Lua keys with Go fields: tags have priority over matching field
	// name.
	fields := map[string]string{}
	st := ref.Type()
	for i := 0; i < ref.NumField(); i++ {
		field := st.Field(i)
		tag := field.Tag.Get("lua")
		if tag != "" {
			fields[tag] = field.Name
			continue
		}
		fields[field.Name] = field.Name
	}

	L.PushNil()
	if idx < 0 {
		idx--
	}
	for L.Next(idx) != 0 {
		key := L.ToString(-2)
		f := ref.FieldByName(fields[key])
		if f.CanSet() && f.IsValid() {
			val := reflect.ValueOf(luaToGo(L, f.Type(), -1, visited))
			f.Set(val)
		}
		L.Pop(1)
	}
	if wasPtr {
		return s.Interface()
	}
	return s.Elem().Interface()
}

// return the Lua table at 'idx' as a copied Go map. If 't' is nil then the map
// type is map[string]interface{}
func CopyTableToMap(L *lua.State, t reflect.Type, idx int) interface{} {
	if t == nil {
		t = reflect.TypeOf(tmap)
	}
	te, tk := t.Elem(), t.Key()
	m := reflect.MakeMap(t)
	L.PushNil()
	if idx < 0 {
		idx--
	}
	for L.Next(idx) != 0 {
		// key at -2, value at -1
		key := valueOf(LuaToGo(L, tk, -2))
		val := valueOf(LuaToGo(L, te, -1))
		m.SetMapIndex(key, val)
		L.Pop(1)
	}
	return m.Interface()
}

// Copy matching Lua table entries to a struct, given the struct type
// and the index on the Lua stack.
func CopyTableToStruct(L *lua.State, t reflect.Type, idx int) interface{} {
	was_ptr := t.Kind() == reflect.Ptr
	if was_ptr {
		t = t.Elem()
	}
	s := reflect.New(t) // T -> *T
	ref := s.Elem()

	// Associate Lua keys with Go fields: tags have priority over matching field
	// name.
	fields := map[string]string{}
	st := ref.Type()
	for i := 0; i < ref.NumField(); i++ {
		field := st.Field(i)
		tag := field.Tag.Get("lua")
		if tag != "" {
			fields[tag] = field.Name
			continue
		}
		fields[field.Name] = field.Name
	}

	L.PushNil()
	if idx < 0 {
		idx--
	}
	for L.Next(idx) != 0 {
		key := L.ToString(-2)
		f := ref.FieldByName(fields[key])
		if f.CanSet() && f.IsValid() {
			val := luaToGoValue(L, f.Type(), -1)
			f.Set(val)
		}
		L.Pop(1)
	}
	if was_ptr {
		return s.Interface()
	}
	return s.Elem().Interface()
}

// Return the Lua table at 'idx' as a copied Go map. If 't' is nil then the map
// type is map[string]interface{}
func CopyTableToMap(L *lua.State, t reflect.Type, idx int) interface{} {
	if t == nil {
		t = tmap
	}
	te, tk := t.Elem(), t.Key()
	m := reflect.MakeMap(t)
	L.PushNil()
	if idx < 0 {
		idx--
	}
	for L.Next(idx) != 0 {
		// key at -2, value at -1
		key := luaToGoValue(L, tk, -2)
		val := luaToGoValue(L, te, -1)
		if val == nullv {
			val = reflect.Zero(te)
		}
		m.SetMapIndex(key, val)
		L.Pop(1)
	}
	return m.Interface()
}