V8 API Reference, 7.2.502.16 (for Deno 0.2.4)
token.h
1 // Copyright 2012 the V8 project authors. All rights reserved.
2 // Use of this source code is governed by a BSD-style license that can be
3 // found in the LICENSE file.
4 
5 #ifndef V8_PARSING_TOKEN_H_
6 #define V8_PARSING_TOKEN_H_
7 
8 #include "src/base/logging.h"
9 #include "src/globals.h"
10 #include "src/utils.h"
11 
12 namespace v8 {
13 namespace internal {
14 
15 // TOKEN_LIST takes a list of 3 macros M, all of which satisfy the
16 // same signature M(name, string, precedence), where name is the
17 // symbolic token name, string is the corresponding syntactic symbol
18 // (or nullptr, for literals), and precedence is the precedence (or 0).
19 // The parameters are invoked for token categories as follows:
20 //
21 // T: Non-keyword tokens
22 // K: Keyword tokens
23 
24 // IGNORE_TOKEN is a convenience macro that can be supplied as
25 // an argument (at any position) for a TOKEN_LIST call. It does
26 // nothing with tokens belonging to the respective category.
27 
28 #define IGNORE_TOKEN(name, string, precedence)
29 
30 /* Binary operators */
31 /* ADD and SUB are at the end since they are UnaryOp */
32 #define BINARY_OP_TOKEN_LIST(T, E) \
33  E(T, BIT_OR, "|", 6) \
34  E(T, BIT_XOR, "^", 7) \
35  E(T, BIT_AND, "&", 8) \
36  E(T, SHL, "<<", 11) \
37  E(T, SAR, ">>", 11) \
38  E(T, SHR, ">>>", 11) \
39  E(T, MUL, "*", 13) \
40  E(T, DIV, "/", 13) \
41  E(T, MOD, "%", 13) \
42  E(T, EXP, "**", 14) \
43  E(T, ADD, "+", 12) \
44  E(T, SUB, "-", 12)
45 
46 #define EXPAND_BINOP_ASSIGN_TOKEN(T, name, string, precedence) \
47  T(ASSIGN_##name, string "=", 2)
48 
49 #define EXPAND_BINOP_TOKEN(T, name, string, precedence) \
50  T(name, string, precedence)
51 
52 #define TOKEN_LIST(T, K, C) \
53  \
54  /* BEGIN PropertyOrCall */ \
55  /* BEGIN Member */ \
56  /* BEGIN Template */ \
57  /* ES6 Template Literals */ \
58  T(TEMPLATE_SPAN, nullptr, 0) \
59  T(TEMPLATE_TAIL, nullptr, 0) \
60  /* END Template */ \
61  \
62  /* Punctuators (ECMA-262, section 7.7, page 15). */ \
63  /* BEGIN Property */ \
64  T(PERIOD, ".", 0) \
65  T(LBRACK, "[", 0) \
66  /* END Property */ \
67  /* END Member */ \
68  T(LPAREN, "(", 0) \
69  /* END PropertyOrCall */ \
70  T(RPAREN, ")", 0) \
71  T(RBRACK, "]", 0) \
72  T(LBRACE, "{", 0) \
73  T(COLON, ":", 0) \
74  T(ELLIPSIS, "...", 0) \
75  T(CONDITIONAL, "?", 3) \
76  /* BEGIN AutoSemicolon */ \
77  T(SEMICOLON, ";", 0) \
78  T(RBRACE, "}", 0) \
79  /* End of source indicator. */ \
80  T(EOS, "EOS", 0) \
81  /* END AutoSemicolon */ \
82  \
83  /* BEGIN ArrowOrAssignmentOp */ \
84  T(ARROW, "=>", 0) \
85  /* BEGIN AssignmentOp */ \
86  /* IsAssignmentOp() relies on this block of enum values being */ \
87  /* contiguous and sorted in the same order! */ \
88  T(INIT, "=init", 2) /* AST-use only. */ \
89  T(ASSIGN, "=", 2) \
90  BINARY_OP_TOKEN_LIST(T, EXPAND_BINOP_ASSIGN_TOKEN) \
91  /* END AssignmentOp */ \
92  /* END ArrowOrAssignmentOp */ \
93  \
94  /* Binary operators sorted by precedence. */ \
95  /* IsBinaryOp() relies on this block of enum values */ \
96  /* being contiguous and sorted in the same order! */ \
97  T(COMMA, ",", 1) \
98  T(OR, "||", 4) \
99  T(AND, "&&", 5) \
100  \
101  /* Unary operators, starting at ADD in BINARY_OP_TOKEN_LIST */ \
102  /* IsUnaryOp() relies on this block of enum values */ \
103  /* being contiguous and sorted in the same order! */ \
104  BINARY_OP_TOKEN_LIST(T, EXPAND_BINOP_TOKEN) \
105  \
106  T(NOT, "!", 0) \
107  T(BIT_NOT, "~", 0) \
108  K(DELETE, "delete", 0) \
109  K(TYPEOF, "typeof", 0) \
110  K(VOID, "void", 0) \
111  \
112  /* BEGIN IsCountOp */ \
113  T(INC, "++", 0) \
114  T(DEC, "--", 0) \
115  /* END IsCountOp */ \
116  /* END IsUnaryOrCountOp */ \
117  \
118  /* Compare operators sorted by precedence. */ \
119  /* IsCompareOp() relies on this block of enum values */ \
120  /* being contiguous and sorted in the same order! */ \
121  T(EQ, "==", 9) \
122  T(EQ_STRICT, "===", 9) \
123  T(NE, "!=", 9) \
124  T(NE_STRICT, "!==", 9) \
125  T(LT, "<", 10) \
126  T(GT, ">", 10) \
127  T(LTE, "<=", 10) \
128  T(GTE, ">=", 10) \
129  K(INSTANCEOF, "instanceof", 10) \
130  K(IN, "in", 10) \
131  \
132  /* Keywords (ECMA-262, section 7.5.2, page 13). */ \
133  K(BREAK, "break", 0) \
134  K(CASE, "case", 0) \
135  K(CATCH, "catch", 0) \
136  K(CONTINUE, "continue", 0) \
137  K(DEBUGGER, "debugger", 0) \
138  K(DEFAULT, "default", 0) \
139  /* DELETE */ \
140  K(DO, "do", 0) \
141  K(ELSE, "else", 0) \
142  K(FINALLY, "finally", 0) \
143  K(FOR, "for", 0) \
144  K(FUNCTION, "function", 0) \
145  K(IF, "if", 0) \
146  /* IN */ \
147  /* INSTANCEOF */ \
148  K(NEW, "new", 0) \
149  K(RETURN, "return", 0) \
150  K(SWITCH, "switch", 0) \
151  K(THROW, "throw", 0) \
152  K(TRY, "try", 0) \
153  /* TYPEOF */ \
154  K(VAR, "var", 0) \
155  /* VOID */ \
156  K(WHILE, "while", 0) \
157  K(WITH, "with", 0) \
158  K(THIS, "this", 0) \
159  \
160  /* Literals (ECMA-262, section 7.8, page 16). */ \
161  K(NULL_LITERAL, "null", 0) \
162  K(TRUE_LITERAL, "true", 0) \
163  K(FALSE_LITERAL, "false", 0) \
164  T(NUMBER, nullptr, 0) \
165  T(SMI, nullptr, 0) \
166  T(BIGINT, nullptr, 0) \
167  T(STRING, nullptr, 0) \
168  \
169  /* BEGIN Callable */ \
170  K(SUPER, "super", 0) \
171  /* BEGIN AnyIdentifier */ \
172  /* Identifiers (not keywords or future reserved words). */ \
173  T(IDENTIFIER, nullptr, 0) \
174  K(ASYNC, "async", 0) \
175  /* `await` is a reserved word in module code only */ \
176  K(AWAIT, "await", 0) \
177  K(YIELD, "yield", 0) \
178  K(LET, "let", 0) \
179  K(STATIC, "static", 0) \
180  /* Future reserved words (ECMA-262, section 7.6.1.2). */ \
181  T(FUTURE_STRICT_RESERVED_WORD, nullptr, 0) \
182  T(ESCAPED_STRICT_RESERVED_WORD, nullptr, 0) \
183  K(ENUM, "enum", 0) \
184  /* END Callable */ \
185  /* END AnyIdentifier */ \
186  K(CLASS, "class", 0) \
187  K(CONST, "const", 0) \
188  K(EXPORT, "export", 0) \
189  K(EXTENDS, "extends", 0) \
190  K(IMPORT, "import", 0) \
191  T(PRIVATE_NAME, nullptr, 0) \
192  \
193  /* Illegal token - not able to scan. */ \
194  T(ILLEGAL, "ILLEGAL", 0) \
195  T(ESCAPED_KEYWORD, nullptr, 0) \
196  \
197  /* Scanner-internal use only. */ \
198  T(WHITESPACE, nullptr, 0) \
199  T(UNINITIALIZED, nullptr, 0) \
200  T(REGEXP_LITERAL, nullptr, 0)
201 
202 class Token {
203  public:
204  // All token values.
205 #define T(name, string, precedence) name,
206  enum Value : uint8_t { TOKEN_LIST(T, T, T) NUM_TOKENS };
207 #undef T
208 
209  // Returns a string corresponding to the C++ token name
210  // (e.g. "LT" for the token LT).
211  static const char* Name(Value token) {
212  DCHECK_GT(NUM_TOKENS, token); // token is unsigned
213  return name_[token];
214  }
215 
216  static char TypeForTesting(Value token) { return token_type[token]; }
217 
218  // Predicates
219  static bool IsKeyword(Value token) { return token_type[token] == 'K'; }
220 
221  static bool IsIdentifier(Value token, LanguageMode language_mode,
222  bool is_generator, bool disallow_await) {
223  if (IsInRange(token, IDENTIFIER, ASYNC)) return true;
224  if (IsInRange(token, LET, ESCAPED_STRICT_RESERVED_WORD)) {
225  return is_sloppy(language_mode);
226  }
227  if (token == AWAIT) return !disallow_await;
228  if (token == YIELD) return !is_generator && is_sloppy(language_mode);
229  return false;
230  }
231 
232  static bool IsCallable(Value token) { return IsInRange(token, SUPER, ENUM); }
233 
234  static bool IsAutoSemicolon(Value token) {
235  return IsInRange(token, SEMICOLON, EOS);
236  }
237 
238  static bool IsAnyIdentifier(Value token) {
239  return IsInRange(token, IDENTIFIER, ENUM);
240  }
241 
242  static bool IsStrictReservedWord(Value token) {
243  return IsInRange(token, LET, ESCAPED_STRICT_RESERVED_WORD);
244  }
245 
246  static bool IsLiteral(Value token) {
247  return IsInRange(token, NULL_LITERAL, STRING);
248  }
249 
250  static bool IsTemplate(Value token) {
251  return IsInRange(token, TEMPLATE_SPAN, TEMPLATE_TAIL);
252  }
253 
254  static bool IsMember(Value token) {
255  return IsInRange(token, TEMPLATE_SPAN, LBRACK);
256  }
257 
258  static bool IsProperty(Value token) {
259  return IsInRange(token, PERIOD, LBRACK);
260  }
261 
262  static bool IsPropertyOrCall(Value token) {
263  return IsInRange(token, TEMPLATE_SPAN, LPAREN);
264  }
265 
266  static bool IsArrowOrAssignmentOp(Value token) {
267  return IsInRange(token, ARROW, ASSIGN_SUB);
268  }
269 
270  static bool IsAssignmentOp(Value token) {
271  return IsInRange(token, INIT, ASSIGN_SUB);
272  }
273 
274  static bool IsBinaryOp(Value op) { return IsInRange(op, COMMA, SUB); }
275 
276  static bool IsCompareOp(Value op) { return IsInRange(op, EQ, IN); }
277 
278  static bool IsOrderedRelationalCompareOp(Value op) {
279  return IsInRange(op, LT, GTE);
280  }
281 
282  static bool IsEqualityOp(Value op) { return IsInRange(op, EQ, EQ_STRICT); }
283 
284  static Value BinaryOpForAssignment(Value op) {
285  DCHECK(IsInRange(op, ASSIGN_BIT_OR, ASSIGN_SUB));
286  Value result = static_cast<Value>(op - ASSIGN_BIT_OR + BIT_OR);
287  DCHECK(IsBinaryOp(result));
288  return result;
289  }
290 
291  static bool IsBitOp(Value op) {
292  return IsInRange(op, BIT_OR, SHR) || op == BIT_NOT;
293  }
294 
295  static bool IsUnaryOp(Value op) { return IsInRange(op, ADD, VOID); }
296  static bool IsCountOp(Value op) { return IsInRange(op, INC, DEC); }
297  static bool IsUnaryOrCountOp(Value op) { return IsInRange(op, ADD, DEC); }
298  static bool IsShiftOp(Value op) { return IsInRange(op, SHL, SHR); }
299 
300  // Returns a string corresponding to the JS token string
301  // (.e., "<" for the token LT) or nullptr if the token doesn't
302  // have a (unique) string (e.g. an IDENTIFIER).
303  static const char* String(Value token) {
304  DCHECK_GT(NUM_TOKENS, token); // token is unsigned
305  return string_[token];
306  }
307 
308  static uint8_t StringLength(Value token) {
309  DCHECK_GT(NUM_TOKENS, token); // token is unsigned
310  return string_length_[token];
311  }
312 
313  // Returns the precedence > 0 for binary and compare
314  // operators; returns 0 otherwise.
315  static int Precedence(Value token, bool accept_IN) {
316  DCHECK_GT(NUM_TOKENS, token); // token is unsigned
317  return precedence_[accept_IN][token];
318  }
319 
320  private:
321  static const char* const name_[NUM_TOKENS];
322  static const char* const string_[NUM_TOKENS];
323  static const uint8_t string_length_[NUM_TOKENS];
324  static const int8_t precedence_[2][NUM_TOKENS];
325  static const char token_type[NUM_TOKENS];
326 };
327 
328 } // namespace internal
329 } // namespace v8
330 
331 #endif // V8_PARSING_TOKEN_H_
v8
Definition: libplatform.h:13