the beginning of a new interpreter

2026-07-26 21:08:45 +08:00 · 2020-05-31 10:19:26 -07:00
parent 2bb4ece7b7
commit e1d23baef3
16 changed files with 771 additions and 0 deletions
@@ -0,0 +1,99 @@
+#ifndef __NASAL_LEXER_H__
+#define __NASAL_LEXER_H__
+
+#define IS_IDENTIFIER_HEAD(c) (c=='_')||('a'<=c && c<='z')||('A'<=c&&c<='Z')
+#define IS_IDENTIFIER_BODY(c) (c=='_')||('a'<=c && c<='z')||('A'<=c&&c<='Z')||('0'<=c&&c<='9')
+#define IS_NUMBER_HEAD(c)     ('0'<=c&&c<='9')
+#define IS_NUMBER_BODY(c)     ('0'<=c&&c<='9')||('a'<=c&&c<='f')||('A'<=c&&c<='F')||(c=='e'||c=='E'||c=='.'||c=='x'||c=='o')
+#define IS_STRING_HEAD(c)     (c=='\''||c=='\"')
+// single operators have only one character
+#define IS_SINGLE_OPRATOR(c)  (c=='('||c==')'||c=='['||c==']'||c=='{'||c=='}'||c==','||c==';'||c=='|'||c==':'||\
+							   c=='?'||c=='`'||c=='&'||c=='@'||c=='%'||c=='$'||c=='^'||c=='\\')
+#define IS_DOT(c)             (c=='.')
+// calculation operators may have two chars, for example: += -= *= /= ~= != == >= <=
+#define IS_CALC_OPERATOR(c)   (c=='='||c=='+'||c=='-'||c=='*'||c=='!'||c=='/'||c=='<'||c=='>'||c=='~')
+#define IS_NOTE_HEAD(c)       (c=='#')
+
+#ifndef TOKEN_TABLE_SIZE
+#define TOKEN_TABLE_SIZE 44
+struct token_table
+{
+    std::string str;
+    int tok_type;
+}tok_tbl[TOKEN_TABLE_SIZE]=
+{
+    {"for"     ,tok_for          },
+    {"forindex",tok_forindex     },
+    {"foreach" ,tok_foreach      },
+    {"while"   ,tok_while        },
+    {"var"     ,tok_var          },
+    {"func"    ,tok_func         },
+    {"break"   ,tok_break        },
+    {"continue",tok_continue     },
+    {"return"  ,tok_return       },
+    {"if"      ,tok_if           },
+    {"elsif"   ,tok_elsif        },
+    {"else"    ,tok_else         },
+    {"nil"     ,tok_nil          },
+    {"("       ,tok_left_curve   },
+    {")"       ,tok_right_curve  },
+    {"["       ,tok_left_bracket },
+    {"]"       ,tok_right_bracket},
+    {"{"       ,tok_left_brace   },
+    {"}"       ,tok_right_brace  },
+    {";"       ,tok_semi         },
+    {"and"     ,tok_and          },
+    {"or"      ,tok_or           },
+    {","       ,tok_comma        },
+    {"."       ,tok_dot          },
+    {"..."     ,tok_ellipsis     },
+    {"?"       ,tok_quesmark     },
+    {":"       ,tok_colon        },
+    {"+"       ,tok_add          },
+    {"-"       ,tok_sub          },
+    {"*"       ,tok_mult         },
+    {"/"       ,tok_div          },
+    {"~"       ,tok_link         },
+    {"!"       ,tok_not          },
+    {"+="      ,tok_add_equal    },
+    {"-="      ,tok_sub_equal    },
+    {"*="      ,tok_mult_equal   },
+    {"/="      ,tok_div_equal    },
+    {"~="      ,tok_link_equal   },
+    {"=="      ,tok_cmp_equal    },
+    {"!="      ,tok_cmp_not_equal},
+    {"<"       ,tok_less_than    },
+    {">"       ,tok_greater_than },
+    {"<="      ,tok_less_equal   },
+    {">="      ,tok_greater_equal},
+};
+#endif
+
+struct token
+{
+    int line;
+    int type;
+    std::string str;
+};
+
+class nasal_lexer
+{
+private:
+    std::vector<token> token_list;
+public:
+    void delete_tokens();
+    void scanner(std::vector<char>&);
+};
+
+void nasal_lexer::delete_tokens()
+{
+    token_list.clear();
+    return;
+}
+
+void nasal_lexer::scanner(std::vector<char>& res)
+{
+    return;
+}
+
+#endif