如何在VIM中将语法高亮颜色设置为语法脚本中的局部变量值？

Question

我想做的事情如下：

"define our language struct variables with their default syntax color values
let s:procedural_fg = "Red"
let s:declarative_fg = "Blue"
let s:string_fg = "DarkGray"

...

"Now the actual highlighting directives based on the groups defined elsewhere
hi cyLoops guifg=s:procedural_fg
hi cyConstants guifg=s:declarative_fg
hi cyString guifg=s:string_fg

但是VIM不允许我这样设置guifg值（“错误：不能为每个变量名称分配颜色s：procedural_fg”......等等）。我想定义以这种方式突出显示的语法，以便可以通过更改局部变量值然后刷新缓冲区（或者应用新颜色值所需的任何内容）来动态更改它。

这可以在VIM语法脚本中完成吗？如果是这样，怎么样？

我已经尝试了几种变体：

"define our language struct variables with their default syntax color values
let s:procedural_fg = Red
let s:declarative_fg = Blue
let s:string_fg = DarkGray

...

"Now the actual highlighting directives based on the groups defined elsewhere
hi cyLoops guifg=s:procedural_fg
hi cyConstants guifg=s:declarative_fg
hi cyString guifg=s:string_fg

和

"define our language struct variables with their default syntax color values
let s:procedural_fg = v:Red
let s:declarative_fg = v:Blue
let s:string_fg = v:DarkGray

...

"Now the actual highlighting directives based on the groups defined elsewhere
hi cyLoops guifg=s:procedural_fg
hi cyConstants guifg=s:declarative_fg
hi cyString guifg=s:string_fg

导致出错，抱怨Red，Blue等或v：Red，v：Blue等未定义和/或表达无效。

感谢， CCJ

Answer 1

使用:exec，这对于Vim来说是eval对于Perl或bash shell：

:exec 'hi cyLoops guifg=' . s:procedural_fg