如何修复节点终端中的"变量未定义"，为什么会发生这种情况？

Question

我定义了一个变量，并给它分配了一个语法错误的函数。它抛出错误。现在，我无法将该变量用于任何事情，它总是说'抛出：引用错误：未定义变量'

> let bg = 'asasas-123d'
undefined
> let fd = bg.substring(indexOf('-')+1)
Thrown:
ReferenceError: indexOf is not defined
> let fd = bg.substring(bg.indexOf('-')+1)
Thrown:
SyntaxError: Identifier 'fd' has already been declared
>  fd = bg.substring(bg.indexOf('-')+1)
Thrown:
ReferenceError: fd is not defined
> let  fd = bg.substring(bg.indexOf('-')+1)
Thrown:
SyntaxError: Identifier 'fd' has already been declared
> fd = bg.substring(bg.indexOf('-')+1)
Thrown:
ReferenceError: fd is not defined
> fd
Thrown:
ReferenceError: fd is not defined
> console.log(fd);
Thrown:
ReferenceError: fd is not defined

Answer 1

只需重新启动终端并运行以下命令：

> let bg = 'asasas-123d'
> let fd = bg.substring(bg.indexOf("-") + 1))