修改 Lua支持中文变量名

1. 找到 LuaPlus 工程下的 Lua Source Files 下的 llex.c；

2. 在该文件中找到下面所列函数；

static int llex (LexState *ls, SemInfo *seminfo)

3. 这是 Lua 的语法分析模块的关键函数，它由一长段 switch 构成，在一串 case 后找到 default 分支

4. 在该分支下找到如下代码段，这是一段完整的 if 分支，该代码段负责将符合条件的字符组合识别为 identifier （函数名或变量名）或 keyword （关键字）

else if (isalpha(ls->current) || ls->current == ‘_‘) {
02.          /* identifier or reserved word */
03.          TString *ts;
04.          if (ls->current == ‘L‘) {
05.            next(ls);
06.            if (ls->current == ‘"‘ || ls->current == ‘/‘‘) {
07.              read_wstring(ls, ls->current, seminfo);
08.              return TK_WSTRING;
09.            }
10.            save(ls, ‘L‘);
11.          }
12.          /* identifier or reserved word */
13.          do {
14.            save_and_next(ls);
15.          } while (isalnum(ls->current) || ls->current == ‘_‘);
16.          ts = luaX_newstring(ls, luaZ_buffer(ls->buff),
17.                                  luaZ_bufflen(ls->buff));
18.          if (ts->tsv.reserved > 0)  /* reserved word? */
19.            return ts->tsv.reserved - 1 + FIRST_RESERVED;
20.          else {
21.            seminfo->ts = ts;
22.            return TK_NAME;
23.          }
24.        }

5. 将该段替换为下面这一段即可，其作用在于加入了对中文ASCII字符的识别

else if (isalpha(ls->current) || ls->current == ‘_‘ || ls->current > 0x80) {
02.          /* identifier or reserved word */
03.          TString *ts;
04.          if (ls->current == ‘L‘) {
05.            next(ls);
06.            if (ls->current == ‘"‘ || ls->current == ‘/‘‘) {
07.              read_wstring(ls, ls->current, seminfo);
08.              return TK_WSTRING;
09.            }
10.            save(ls, ‘L‘);
11.          }
12.          /* identifier or reserved word */
13.          do {
14.              if(ls->current > 0x80)
15.              {
16.                 save_and_next(ls);
17.                 save_and_next(ls);
18.              }
19.              else
20.                 save_and_next(ls);
21.          } while (isalnum(ls->current) || ls->current == ‘_‘ || ls->current > 0x80);
22.          ts = luaX_newstring(ls, luaZ_buffer(ls->buff),
23.                                  luaZ_bufflen(ls->buff));
24.          if (ts->tsv.reserved > 0)  /* reserved word? */
25.            return ts->tsv.reserved - 1 + FIRST_RESERVED;
26.          else {
27.            seminfo->ts = ts;
28.            return TK_NAME;
29.          }
30.        }