如何將VIM中的語法高亮顏色設置爲語法腳本中局部變量的值？

Question

我想要做的是類似如下：

"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VIM不會讓我設置guifg值這種方式（「錯誤：無法分配顏色S：procedural_fg」 ......和每個變量名稱都是如此）。我想定義突出顯示這種方式的語法，以便通過更改局部變量值然後刷新緩衝區（或適用新顏色值所需的任何值）來動態更改它。

這可以在VIM語法腳本中完成嗎？如果是這樣，怎麼樣？

我已經嘗試了幾種變化：

"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 

從而導致錯誤抱怨，紅色，藍色等，或v：紅色，V：藍等都是未定義和/或無效的表達式。

感謝， CCJ

Answer 1

使用:exec，這是Vim如何eval是Perl或bash shell中：

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