Initialize an empty stack and empty result string variable.

初始化一个空堆栈，将结果字符串变量置空。

youdao

Its only argument is the address of the string to be displayed, which is passed on to it by pushing the address of the string in the stack (line 30).

它惟一的参数是要显示的字符串的地址，通过将字符串的地址压入堆栈(第30行)，将这个参数传递给它。

youdao

If an error occurs during execution, a Lua string is pushed on the stack.

如果在执行时出现了错误，就向堆栈中压入一个lua字符串。

youdao

This is main string here on the stack.

这个是在堆栈中的主字符串。

哈佛公开课 - 计算机科学课程节选