:help sub-replace-expression(强调我的想法)

当替换字符串以"\ ="开头时，其余部分将被解释为 表达.

When the substitute string starts with "\=" the remainder is interpreted as an expression.

您不能做自己想做的事；替换字符串要么是子表达式(以\=开头)，要么是文字(如果不是).

You cannot do what you want; the replacement string is either a subexpression (when it starts with \=), or a literal (when it does not).

相反，您需要重写子表达式以编程方式连接字符串(:help expr-.):

Instead, you need to rewrite the subexpression to concatenate the string programmatically (:help expr-.):

:let n=[0] | %s/|-\n|/\="BLABLA".map(n,'v:val+1')[0]/g

[0]接受由map生成的数组的内容是必要的，原因有两个:用数组替换将引入不需要的换行符，并使得无法与字符串连接.

[0] to take the content of the array produced by map is necessary for two reasons: replacing with an array will introduce an unwanted newline, and make concatenation with a string impossible.

但是对于您的示例，如果您没有引入除数字之外的任何字符串，则可能没有必要-即，如果您不需要该空格(:help /\zs):

For your example though, it may not necessary, if you are not introducing any string besides the number - i.e. if you don't need that space (:help /\zs):

:let n=[0] | %s/|-\n|\zs/\=map(n,'v:val+1')[0]/g

当然，您可以将两者结合起来，以针对您的特定情况提供完美的去离子化解决方案:

Of course, you can combine the two, for a perfect demoisturised solution to your specific situation:

:let n=[0] | %s/|-\n|\zs/\=" ".map(n,'v:val+1')[0]/g