的Lua - 表的长度似乎无效

Question

a = {} 
a[1] = 1 
a[2] = nil -- does nothing, as a[2] is already nil 
a[3] = 14 

print(#a) 

打印1

a = {} 
a[1] = 1 
a[2] = nil -- does nothing, as a[2] is already nil 
a[3] = 14 
a[4] = 5 

print(#a) 

打印4

什么是＃运营商真正回归？

Answer 1

如果表格不正确，则应用于该表格的#运算符的返回值未定义。

在这两种情况下，a都不是正确的顺序，因为a[2] == nil和a[3] ~= nil。

#运算符返回正确序列的长度。