emacs lisp有沒有辦法改善這個正則表達式

Question

我希望這個正則表達式將每個術語放在大括號內。但是，如果沒有與逃生參數項串連這個詞與下一屆

(replace-regexp-in-string "{ " "{" 
(replace-regexp-in-string "}{" "} {" (replace-regexp-in-string  
"\\(.*?_.\\)" "{\\1}" "\Delta y_t u_t"))) 

所需的輸出

y_t a_t ==> {y_t} {a_t} 
\Delta y_t a_t ==> {\Delta y_t} {a_t} 

Answer 1

試試這個，你可能需要調整反斜線數量

(replace-regexp-in-string "}{" "} {" (replace-regexp-in-string  
"\(\(?:\\\w+ \)?\w+\)" "{\\1}" "\Delta y_t u_t"))) 

Answer 2

您可以嘗試

(replace-regexp-in-string 
    "\\(\\(?:\\\\[^ \t]+[ \t]\\)?[^ \t]+\\)" "{\\1}" "z_t \\Delta y_t x_t") 

使用與上一個答案相同類型的可選捕獲組。