NASM說明書(v2.14.02)翻譯-3.4.2 數字常量

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3.4.2 字符流(Character Strings)¹常量

由單引號''、雙引號""、反引號``包裹的最多八個字符組成一個字符流。雙引號和單引號沒有區別（只是雙引號裏的字符流可以包含單引號，反之亦然）。

      \'          single quote (') 
      \"          double quote (") 
      \`          backquote (`) 
      \\          backslash (\) 
      \?          question mark (?) 
      \a          BEL (ASCII 7) 
      \b          BS  (ASCII 8) 
      \t          TAB (ASCII 9) 
      \n          LF  (ASCII 10) 
      \v          VT  (ASCII 11) 
      \f          FF  (ASCII 12) 
      \r          CR  (ASCII 13) 
      \e          ESC (ASCII 27) 
      \377        Up to 3 octal digits - literal byte 
      \xFF        Up to 2 hexadecimal digits - literal byte 
      \u1234      4 hexadecimal digits - Unicode character 
      \U12345678  8 hexadecimal digits - Unicode character

其他所有的轉義都被保留。注意\0代表NUL（ASCII 0），是八進制轉義的一個特例。
\u或\U指定的Unicode字符會被轉變成UTF-8。例如下面的代碼都是等價的。

      db `\u263a`            ; UTF-8 smiley face 
      db `\xe2\x98\xba`      ; UTF-8 smiley face 
      db 0E2h, 098h, 0BAh    ; UTF-8 smiley face

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1. 並不是字符串常量。雖然不明白它與字符串常量的區別，但是NASM的文檔裏就是這麼寫的。
   單引號和雙引號字符流常量按原樣彙編。反引號字符流常量，支持C語言風格的轉義字符。
   以下爲支持的轉義 ↩︎