Method indexToValue

lua.go:491–516

(index int)

var none value = &struct{}{}

func (l *State) indexToValue(index int) value {
	switch {
	case index > 0:
		// TODO apiCheck(index <= callInfo.top_-(callInfo.function+1), "unacceptable index")
		// if i := callInfo.function + index; i < l.top {
		// 	return l.stack[i]
		// }
		// return none
		if l.callInfo.function+index >= l.top {
			return none
		}
		return l.stack[l.callInfo.function:l.top][index]
	case index > RegistryIndex: // negative index
		// TODO apiCheck(index != 0 && -index <= l.top-(callInfo.function+1), "invalid index")
		return l.stack[l.top+index]
	case index == RegistryIndex:
		return l.global.registry
	default: // upvalues
		i := RegistryIndex - index
		return l.stack[l.callInfo.function].(*goClosure).upValues[i-1]
		// if closure := l.stack[callInfo.function].(*goClosure); i <= len(closure.upValues) {
		// 	return closure.upValues[i-1]
		// }
		// return none
	}
}

func (l *State) setIndexToValue(index int, v value) {
	switch {