| // Copyright (c) 2016, the Dart project authors. Please see the AUTHORS file |
| // for details. All rights reserved. Use of this source code is governed by a |
| // BSD-style license that can be found in the LICENSE file. |
| |
| /** |
| * Defines the tokens that are produced by the scanner, used by the parser, and |
| * referenced from the [AST structure](ast.dart). |
| */ |
| import 'dart:collection'; |
| |
| import '../base/syntactic_entity.dart'; |
| import 'string_utilities.dart'; |
| import 'token_constants.dart'; |
| |
| const int NO_PRECEDENCE = 0; |
| const int ASSIGNMENT_PRECEDENCE = 1; |
| const int CASCADE_PRECEDENCE = 2; |
| const int CONDITIONAL_PRECEDENCE = 3; |
| const int IF_NULL_PRECEDENCE = 4; |
| const int LOGICAL_OR_PRECEDENCE = 5; |
| const int LOGICAL_AND_PRECEDENCE = 6; |
| const int EQUALITY_PRECEDENCE = 7; |
| const int RELATIONAL_PRECEDENCE = 8; |
| const int BITWISE_OR_PRECEDENCE = 9; |
| const int BITWISE_XOR_PRECEDENCE = 10; |
| const int BITWISE_AND_PRECEDENCE = 11; |
| const int SHIFT_PRECEDENCE = 12; |
| const int ADDITIVE_PRECEDENCE = 13; |
| const int MULTIPLICATIVE_PRECEDENCE = 14; |
| const int PREFIX_PRECEDENCE = 15; |
| const int POSTFIX_PRECEDENCE = 16; |
| const int SELECTOR_PRECEDENCE = 17; |
| |
| /** |
| * The opening half of a grouping pair of tokens. This is used for curly |
| * brackets ('{'), parentheses ('('), and square brackets ('['). |
| */ |
| class BeginToken extends SimpleToken { |
| /** |
| * The token that corresponds to this token. |
| */ |
| Token? endToken; |
| |
| /** |
| * Initialize a newly created token to have the given [type] at the given |
| * [offset]. |
| */ |
| BeginToken(TokenType type, int offset, [CommentToken? precedingComment]) |
| : super(type, offset, precedingComment) { |
| assert(type == TokenType.LT || |
| type == TokenType.OPEN_CURLY_BRACKET || |
| type == TokenType.OPEN_PAREN || |
| type == TokenType.OPEN_SQUARE_BRACKET || |
| type == TokenType.STRING_INTERPOLATION_EXPRESSION); |
| } |
| |
| @override |
| Token copy() => new BeginToken(type, offset, copyComments(precedingComments)); |
| |
| @override |
| Token? get endGroup => endToken; |
| |
| /** |
| * Set the token that corresponds to this token. |
| */ |
| set endGroup(Token? token) { |
| endToken = token; |
| } |
| } |
| |
| /** |
| * A token representing a comment. |
| */ |
| class CommentToken extends StringToken { |
| /** |
| * The token that contains this comment. |
| */ |
| SimpleToken? parent; |
| |
| /** |
| * Initialize a newly created token to represent a token of the given [type] |
| * with the given [value] at the given [offset]. |
| */ |
| CommentToken(TokenType type, String value, int offset) |
| : super(type, value, offset); |
| |
| @override |
| CommentToken copy() => new CommentToken(type, _value, offset); |
| |
| /** |
| * Remove this comment token from the list. |
| * |
| * This is used when we decide to interpret the comment as syntax. |
| */ |
| void remove() { |
| Token? previous = this.previous; |
| if (previous != null) { |
| previous.setNextWithoutSettingPrevious(next); |
| next?.previous = previous; |
| } else { |
| assert(parent!.precedingComments == this); |
| parent!.precedingComments = next as CommentToken?; |
| } |
| } |
| } |
| |
| /** |
| * A documentation comment token. |
| */ |
| class DocumentationCommentToken extends CommentToken { |
| /** |
| * Initialize a newly created token to represent a token of the given [type] |
| * with the given [value] at the given [offset]. |
| */ |
| DocumentationCommentToken(TokenType type, String value, int offset) |
| : super(type, value, offset); |
| |
| @override |
| CommentToken copy() => new DocumentationCommentToken(type, _value, offset); |
| } |
| |
| enum KeywordStyle { |
| reserved, |
| builtIn, |
| pseudo, |
| } |
| |
| /** |
| * The keywords in the Dart programming language. |
| * |
| * Clients may not extend, implement or mix-in this class. |
| */ |
| class Keyword extends TokenType { |
| static const Keyword ABSTRACT = const Keyword( |
| "abstract", "ABSTRACT", KeywordStyle.builtIn, |
| isModifier: true); |
| |
| static const Keyword AS = const Keyword("as", "AS", KeywordStyle.builtIn, |
| precedence: RELATIONAL_PRECEDENCE); |
| |
| static const Keyword ASSERT = |
| const Keyword("assert", "ASSERT", KeywordStyle.reserved); |
| |
| static const Keyword ASYNC = |
| const Keyword("async", "ASYNC", KeywordStyle.pseudo); |
| |
| static const Keyword AWAIT = |
| const Keyword("await", "AWAIT", KeywordStyle.pseudo); |
| |
| static const Keyword BREAK = |
| const Keyword("break", "BREAK", KeywordStyle.reserved); |
| |
| static const Keyword CASE = |
| const Keyword("case", "CASE", KeywordStyle.reserved); |
| |
| static const Keyword CATCH = |
| const Keyword("catch", "CATCH", KeywordStyle.reserved); |
| |
| static const Keyword CLASS = const Keyword( |
| "class", "CLASS", KeywordStyle.reserved, |
| isTopLevelKeyword: true); |
| |
| static const Keyword CONST = |
| const Keyword("const", "CONST", KeywordStyle.reserved, isModifier: true); |
| |
| static const Keyword CONTINUE = |
| const Keyword("continue", "CONTINUE", KeywordStyle.reserved); |
| |
| static const Keyword COVARIANT = const Keyword( |
| "covariant", "COVARIANT", KeywordStyle.builtIn, |
| isModifier: true); |
| |
| static const Keyword DEFAULT = |
| const Keyword("default", "DEFAULT", KeywordStyle.reserved); |
| |
| static const Keyword DEFERRED = |
| const Keyword("deferred", "DEFERRED", KeywordStyle.builtIn); |
| |
| static const Keyword DO = const Keyword("do", "DO", KeywordStyle.reserved); |
| |
| static const Keyword DYNAMIC = |
| const Keyword("dynamic", "DYNAMIC", KeywordStyle.builtIn); |
| |
| static const Keyword ELSE = |
| const Keyword("else", "ELSE", KeywordStyle.reserved); |
| |
| static const Keyword ENUM = const Keyword( |
| "enum", "ENUM", KeywordStyle.reserved, |
| isTopLevelKeyword: true); |
| |
| static const Keyword EXPORT = const Keyword( |
| "export", "EXPORT", KeywordStyle.builtIn, |
| isTopLevelKeyword: true); |
| |
| static const Keyword EXTENDS = |
| const Keyword("extends", "EXTENDS", KeywordStyle.reserved); |
| |
| static const Keyword EXTENSION = const Keyword( |
| "extension", "EXTENSION", KeywordStyle.builtIn, |
| isTopLevelKeyword: true); |
| |
| static const Keyword EXTERNAL = const Keyword( |
| "external", "EXTERNAL", KeywordStyle.builtIn, |
| isModifier: true); |
| |
| static const Keyword FACTORY = |
| const Keyword("factory", "FACTORY", KeywordStyle.builtIn); |
| |
| static const Keyword FALSE = |
| const Keyword("false", "FALSE", KeywordStyle.reserved); |
| |
| static const Keyword FINAL = |
| const Keyword("final", "FINAL", KeywordStyle.reserved, isModifier: true); |
| |
| static const Keyword FINALLY = |
| const Keyword("finally", "FINALLY", KeywordStyle.reserved); |
| |
| static const Keyword FOR = const Keyword("for", "FOR", KeywordStyle.reserved); |
| |
| static const Keyword FUNCTION = |
| const Keyword("Function", "FUNCTION", KeywordStyle.pseudo); |
| |
| static const Keyword GET = const Keyword("get", "GET", KeywordStyle.builtIn); |
| |
| static const Keyword HIDE = |
| const Keyword("hide", "HIDE", KeywordStyle.pseudo); |
| |
| static const Keyword IF = const Keyword("if", "IF", KeywordStyle.reserved); |
| |
| static const Keyword IMPLEMENTS = |
| const Keyword("implements", "IMPLEMENTS", KeywordStyle.builtIn); |
| |
| static const Keyword IMPORT = const Keyword( |
| "import", "IMPORT", KeywordStyle.builtIn, |
| isTopLevelKeyword: true); |
| |
| static const Keyword IN = const Keyword("in", "IN", KeywordStyle.reserved); |
| |
| static const Keyword INOUT = |
| const Keyword("inout", "INOUT", KeywordStyle.pseudo); |
| |
| static const Keyword INTERFACE = |
| const Keyword("interface", "INTERFACE", KeywordStyle.builtIn); |
| |
| static const Keyword IS = const Keyword("is", "IS", KeywordStyle.reserved, |
| precedence: RELATIONAL_PRECEDENCE); |
| |
| static const Keyword LATE = |
| const Keyword("late", "LATE", KeywordStyle.builtIn, isModifier: true); |
| |
| static const Keyword LIBRARY = const Keyword( |
| "library", "LIBRARY", KeywordStyle.builtIn, |
| isTopLevelKeyword: true); |
| |
| static const Keyword MIXIN = const Keyword( |
| "mixin", "MIXIN", KeywordStyle.builtIn, |
| isTopLevelKeyword: true); |
| |
| static const Keyword NATIVE = |
| const Keyword("native", "NATIVE", KeywordStyle.pseudo); |
| |
| static const Keyword NEW = const Keyword("new", "NEW", KeywordStyle.reserved); |
| |
| static const Keyword NULL = |
| const Keyword("null", "NULL", KeywordStyle.reserved); |
| |
| static const Keyword OF = const Keyword("of", "OF", KeywordStyle.pseudo); |
| |
| static const Keyword ON = const Keyword("on", "ON", KeywordStyle.pseudo); |
| |
| static const Keyword OPERATOR = |
| const Keyword("operator", "OPERATOR", KeywordStyle.builtIn); |
| |
| static const Keyword OUT = const Keyword("out", "OUT", KeywordStyle.pseudo); |
| |
| static const Keyword PART = const Keyword( |
| "part", "PART", KeywordStyle.builtIn, |
| isTopLevelKeyword: true); |
| |
| static const Keyword PATCH = |
| const Keyword("patch", "PATCH", KeywordStyle.pseudo); |
| |
| static const Keyword REQUIRED = const Keyword( |
| "required", "REQUIRED", KeywordStyle.builtIn, |
| isModifier: true); |
| |
| static const Keyword RETHROW = |
| const Keyword("rethrow", "RETHROW", KeywordStyle.reserved); |
| |
| static const Keyword RETURN = |
| const Keyword("return", "RETURN", KeywordStyle.reserved); |
| |
| static const Keyword SET = const Keyword("set", "SET", KeywordStyle.builtIn); |
| |
| static const Keyword SHOW = |
| const Keyword("show", "SHOW", KeywordStyle.pseudo); |
| |
| static const Keyword SOURCE = |
| const Keyword("source", "SOURCE", KeywordStyle.pseudo); |
| |
| static const Keyword STATIC = |
| const Keyword("static", "STATIC", KeywordStyle.builtIn, isModifier: true); |
| |
| static const Keyword SUPER = |
| const Keyword("super", "SUPER", KeywordStyle.reserved); |
| |
| static const Keyword SWITCH = |
| const Keyword("switch", "SWITCH", KeywordStyle.reserved); |
| |
| static const Keyword SYNC = |
| const Keyword("sync", "SYNC", KeywordStyle.pseudo); |
| |
| static const Keyword THIS = |
| const Keyword("this", "THIS", KeywordStyle.reserved); |
| |
| static const Keyword THROW = |
| const Keyword("throw", "THROW", KeywordStyle.reserved); |
| |
| static const Keyword TRUE = |
| const Keyword("true", "TRUE", KeywordStyle.reserved); |
| |
| static const Keyword TRY = const Keyword("try", "TRY", KeywordStyle.reserved); |
| |
| static const Keyword TYPEDEF = const Keyword( |
| "typedef", "TYPEDEF", KeywordStyle.builtIn, |
| isTopLevelKeyword: true); |
| |
| static const Keyword VAR = |
| const Keyword("var", "VAR", KeywordStyle.reserved, isModifier: true); |
| |
| static const Keyword VOID = |
| const Keyword("void", "VOID", KeywordStyle.reserved); |
| |
| static const Keyword WHILE = |
| const Keyword("while", "WHILE", KeywordStyle.reserved); |
| |
| static const Keyword WITH = |
| const Keyword("with", "WITH", KeywordStyle.reserved); |
| |
| static const Keyword YIELD = |
| const Keyword("yield", "YIELD", KeywordStyle.pseudo); |
| |
| static const List<Keyword> values = const <Keyword>[ |
| ABSTRACT, |
| AS, |
| ASSERT, |
| ASYNC, |
| AWAIT, |
| BREAK, |
| CASE, |
| CATCH, |
| CLASS, |
| CONST, |
| CONTINUE, |
| COVARIANT, |
| DEFAULT, |
| DEFERRED, |
| DO, |
| DYNAMIC, |
| ELSE, |
| ENUM, |
| EXPORT, |
| EXTENDS, |
| EXTENSION, |
| EXTERNAL, |
| FACTORY, |
| FALSE, |
| FINAL, |
| FINALLY, |
| FOR, |
| FUNCTION, |
| GET, |
| HIDE, |
| IF, |
| IMPLEMENTS, |
| IMPORT, |
| IN, |
| INOUT, |
| INTERFACE, |
| IS, |
| LATE, |
| LIBRARY, |
| MIXIN, |
| NATIVE, |
| NEW, |
| NULL, |
| OF, |
| ON, |
| OPERATOR, |
| OUT, |
| PART, |
| PATCH, |
| REQUIRED, |
| RETHROW, |
| RETURN, |
| SET, |
| SHOW, |
| SOURCE, |
| STATIC, |
| SUPER, |
| SWITCH, |
| SYNC, |
| THIS, |
| THROW, |
| TRUE, |
| TRY, |
| TYPEDEF, |
| VAR, |
| VOID, |
| WHILE, |
| WITH, |
| YIELD, |
| ]; |
| |
| /** |
| * A table mapping the lexemes of keywords to the corresponding keyword. |
| */ |
| static final Map<String, Keyword> keywords = _createKeywordMap(); |
| |
| final KeywordStyle keywordStyle; |
| |
| /** |
| * Initialize a newly created keyword. |
| */ |
| const Keyword(String lexeme, String name, this.keywordStyle, |
| {bool isModifier: false, |
| bool isTopLevelKeyword: false, |
| int precedence: NO_PRECEDENCE}) |
| : super(lexeme, name, precedence, KEYWORD_TOKEN, |
| isModifier: isModifier, isTopLevelKeyword: isTopLevelKeyword); |
| |
| @override |
| bool get isBuiltIn => keywordStyle == KeywordStyle.builtIn; |
| |
| @override |
| bool get isPseudo => keywordStyle == KeywordStyle.pseudo; |
| |
| bool get isBuiltInOrPseudo => isBuiltIn || isPseudo; |
| |
| @override |
| bool get isReservedWord => keywordStyle == KeywordStyle.reserved; |
| |
| /** |
| * The name of the keyword type. |
| */ |
| String get name => lexeme.toUpperCase(); |
| |
| @override |
| String toString() => name; |
| |
| /** |
| * Create a table mapping the lexemes of keywords to the corresponding keyword |
| * and return the table that was created. |
| */ |
| static Map<String, Keyword> _createKeywordMap() { |
| LinkedHashMap<String, Keyword> result = |
| new LinkedHashMap<String, Keyword>(); |
| for (Keyword keyword in values) { |
| result[keyword.lexeme] = keyword; |
| } |
| return result; |
| } |
| } |
| |
| /** |
| * A token representing a keyword in the language. |
| */ |
| class KeywordToken extends SimpleToken { |
| @override |
| final Keyword keyword; |
| |
| /** |
| * Initialize a newly created token to represent the given [keyword] at the |
| * given [offset]. |
| */ |
| KeywordToken(this.keyword, int offset, [CommentToken? precedingComment]) |
| : super(keyword, offset, precedingComment); |
| |
| @override |
| Token copy() => |
| new KeywordToken(keyword, offset, copyComments(precedingComments)); |
| |
| @override |
| bool get isIdentifier => keyword.isPseudo || keyword.isBuiltIn; |
| |
| @override |
| bool get isKeyword => true; |
| |
| @override |
| bool get isKeywordOrIdentifier => true; |
| |
| @override |
| Object value() => keyword; |
| } |
| |
| /** |
| * A specialized comment token representing a language version |
| * (e.g. '// @dart = 2.1'). |
| */ |
| class LanguageVersionToken extends CommentToken { |
| /** |
| * The major language version. |
| */ |
| final int major; |
| |
| /** |
| * The minor language version. |
| */ |
| final int minor; |
| |
| LanguageVersionToken.from(String text, int offset, this.major, this.minor) |
| : super(TokenType.SINGLE_LINE_COMMENT, text, offset); |
| |
| @override |
| LanguageVersionToken copy() => |
| new LanguageVersionToken.from(lexeme, offset, major, minor); |
| } |
| |
| /** |
| * A token that was scanned from the input. Each token knows which tokens |
| * precede and follow it, acting as a link in a doubly linked list of tokens. |
| */ |
| class SimpleToken implements Token { |
| /** |
| * The type of the token. |
| */ |
| @override |
| final TokenType type; |
| |
| /** |
| * The offset from the beginning of the file to the first character in the |
| * token. |
| */ |
| @override |
| int offset = 0; |
| |
| /** |
| * The previous token in the token stream. |
| */ |
| @override |
| Token? previous; |
| |
| @override |
| Token? next; |
| |
| /** |
| * The first comment in the list of comments that precede this token. |
| */ |
| CommentToken? _precedingComment; |
| |
| /** |
| * Initialize a newly created token to have the given [type] and [offset]. |
| */ |
| SimpleToken(this.type, this.offset, [this._precedingComment]) { |
| _setCommentParent(_precedingComment); |
| } |
| |
| @override |
| int get charCount => length; |
| |
| @override |
| int get charOffset => offset; |
| |
| @override |
| int get charEnd => end; |
| |
| @override |
| Token? get beforeSynthetic => null; |
| |
| @override |
| set beforeSynthetic(Token? previous) { |
| // ignored |
| } |
| |
| @override |
| int get end => offset + length; |
| |
| @override |
| Token? get endGroup => null; |
| |
| @override |
| bool get isEof => type == TokenType.EOF; |
| |
| @override |
| bool get isIdentifier => false; |
| |
| @override |
| bool get isKeyword => false; |
| |
| @override |
| bool get isKeywordOrIdentifier => isIdentifier; |
| |
| @override |
| bool get isModifier => type.isModifier; |
| |
| @override |
| bool get isOperator => type.isOperator; |
| |
| @override |
| bool get isSynthetic => length == 0; |
| |
| @override |
| bool get isTopLevelKeyword => type.isTopLevelKeyword; |
| |
| @override |
| bool get isUserDefinableOperator => type.isUserDefinableOperator; |
| |
| @override |
| Keyword? get keyword => null; |
| |
| @override |
| int get kind => type.kind; |
| |
| @override |
| int get length => lexeme.length; |
| |
| @override |
| String get lexeme => type.lexeme; |
| |
| @override |
| CommentToken? get precedingComments => _precedingComment; |
| |
| void set precedingComments(CommentToken? comment) { |
| _precedingComment = comment; |
| _setCommentParent(_precedingComment); |
| } |
| |
| @override |
| String? get stringValue => type.stringValue; |
| |
| @override |
| Token copy() => |
| new SimpleToken(type, offset, copyComments(precedingComments)); |
| |
| @override |
| CommentToken? copyComments(CommentToken? token) { |
| if (token == null) { |
| return null; |
| } |
| CommentToken head = token.copy(); |
| Token tail = head; |
| token = token.next as CommentToken?; |
| while (token != null) { |
| tail = tail.setNext(token.copy()); |
| token = token.next as CommentToken?; |
| } |
| return head; |
| } |
| |
| @override |
| bool matchesAny(List<TokenType> types) { |
| for (TokenType type in types) { |
| if (this.type == type) { |
| return true; |
| } |
| } |
| return false; |
| } |
| |
| @override |
| Token setNext(Token token) { |
| next = token; |
| token.previous = this; |
| token.beforeSynthetic = this; |
| return token; |
| } |
| |
| @override |
| Token? setNextWithoutSettingPrevious(Token? token) { |
| next = token; |
| return token; |
| } |
| |
| @override |
| String toString() => lexeme; |
| |
| @override |
| Object value() => lexeme; |
| |
| /** |
| * Sets the `parent` property to `this` for the given [comment] and all the |
| * next tokens. |
| */ |
| void _setCommentParent(CommentToken? comment) { |
| while (comment != null) { |
| comment.parent = this; |
| comment = comment.next as CommentToken?; |
| } |
| } |
| } |
| |
| /** |
| * A token whose value is independent of it's type. |
| */ |
| class StringToken extends SimpleToken { |
| /** |
| * The lexeme represented by this token. |
| */ |
| final String _value; |
| |
| /** |
| * Initialize a newly created token to represent a token of the given [type] |
| * with the given [value] at the given [offset]. |
| */ |
| StringToken(TokenType type, String value, int offset, |
| [CommentToken? precedingComment]) |
| : _value = StringUtilities.intern(value), |
| super(type, offset, precedingComment); |
| |
| @override |
| bool get isIdentifier => identical(kind, IDENTIFIER_TOKEN); |
| |
| @override |
| String get lexeme => _value; |
| |
| @override |
| Token copy() => |
| new StringToken(type, _value, offset, copyComments(precedingComments)); |
| |
| @override |
| String value() => _value; |
| } |
| |
| /** |
| * A synthetic begin token. |
| */ |
| class SyntheticBeginToken extends BeginToken { |
| /** |
| * Initialize a newly created token to have the given [type] at the given |
| * [offset]. |
| */ |
| SyntheticBeginToken(TokenType type, int offset, |
| [CommentToken? precedingComment]) |
| : super(type, offset, precedingComment); |
| |
| @override |
| Token copy() => |
| new SyntheticBeginToken(type, offset, copyComments(precedingComments)); |
| |
| @override |
| bool get isSynthetic => true; |
| |
| @override |
| int get length => 0; |
| } |
| |
| /** |
| * A synthetic keyword token. |
| */ |
| class SyntheticKeywordToken extends KeywordToken { |
| /** |
| * Initialize a newly created token to represent the given [keyword] at the |
| * given [offset]. |
| */ |
| SyntheticKeywordToken(Keyword keyword, int offset) : super(keyword, offset); |
| |
| @override |
| int get length => 0; |
| |
| @override |
| Token copy() => new SyntheticKeywordToken(keyword, offset); |
| } |
| |
| /** |
| * A token whose value is independent of it's type. |
| */ |
| class SyntheticStringToken extends StringToken { |
| final int? _length; |
| |
| /** |
| * Initialize a newly created token to represent a token of the given [type] |
| * with the given [value] at the given [offset]. If the [length] is |
| * not specified, then it defaults to the length of [value]. |
| */ |
| SyntheticStringToken(TokenType type, String value, int offset, [this._length]) |
| : super(type, value, offset); |
| |
| @override |
| Token? beforeSynthetic; |
| |
| @override |
| bool get isSynthetic => true; |
| |
| @override |
| int get length => _length ?? super.length; |
| |
| @override |
| Token copy() => new SyntheticStringToken(type, _value, offset, _length); |
| } |
| |
| /** |
| * A synthetic token. |
| */ |
| class SyntheticToken extends SimpleToken { |
| SyntheticToken(TokenType type, int offset) : super(type, offset); |
| |
| @override |
| Token? beforeSynthetic; |
| |
| @override |
| bool get isSynthetic => true; |
| |
| @override |
| int get length => 0; |
| |
| @override |
| Token copy() => new SyntheticToken(type, offset); |
| } |
| |
| /// A token used to replace another token in the stream, while still keeping the |
| /// old token around (in [replacedToken]). Automatically sets the offset and |
| /// precedingComments from the data available on [replacedToken]. |
| class ReplacementToken extends SyntheticToken { |
| /// The token that this token replaces. This will normally be the token |
| /// representing what the user actually wrote. |
| final Token replacedToken; |
| |
| ReplacementToken(TokenType type, this.replacedToken) |
| : super(type, replacedToken.offset) { |
| precedingComments = replacedToken.precedingComments; |
| } |
| |
| @override |
| Token? beforeSynthetic; |
| |
| @override |
| bool get isSynthetic => true; |
| |
| @override |
| int get length => 0; |
| |
| @override |
| Token copy() => new ReplacementToken(type, replacedToken); |
| } |
| |
| /** |
| * A token that was scanned from the input. Each token knows which tokens |
| * precede and follow it, acting as a link in a doubly linked list of tokens. |
| * |
| * Clients may not extend, implement or mix-in this class. |
| */ |
| abstract class Token implements SyntacticEntity { |
| /** |
| * Initialize a newly created token to have the given [type] and [offset]. |
| */ |
| factory Token(TokenType type, int offset, [CommentToken? preceedingComment]) = |
| SimpleToken; |
| |
| /** |
| * Initialize a newly created end-of-file token to have the given [offset]. |
| */ |
| factory Token.eof(int offset, [CommentToken? precedingComments]) { |
| Token eof = new SimpleToken(TokenType.EOF, offset, precedingComments); |
| // EOF points to itself so there's always infinite look-ahead. |
| eof.previous = eof; |
| eof.next = eof; |
| return eof; |
| } |
| |
| /** |
| * The number of characters parsed by this token. |
| */ |
| int get charCount; |
| |
| /** |
| * The character offset of the start of this token within the source text. |
| */ |
| int get charOffset; |
| |
| /** |
| * The character offset of the end of this token within the source text. |
| */ |
| int get charEnd; |
| |
| /** |
| * The token before this synthetic token, |
| * or `null` if this is not a synthetic `)`, `]`, `}`, or `>` token. |
| */ |
| Token? get beforeSynthetic; |
| |
| /** |
| * Set token before this synthetic `)`, `]`, `}`, or `>` token, |
| * and ignored otherwise. |
| */ |
| set beforeSynthetic(Token? previous); |
| |
| @override |
| int get end; |
| |
| /** |
| * The token that corresponds to this token, or `null` if this token is not |
| * the first of a pair of matching tokens (such as parentheses). |
| */ |
| Token? get endGroup => null; |
| |
| /** |
| * Return `true` if this token represents an end of file. |
| */ |
| bool get isEof; |
| |
| /** |
| * True if this token is an identifier. Some keywords allowed as identifiers, |
| * see implementation in [KeywordToken]. |
| */ |
| bool get isIdentifier; |
| |
| /** |
| * True if this token is a keyword. Some keywords allowed as identifiers, |
| * see implementation in [KeywordToken]. |
| */ |
| bool get isKeyword; |
| |
| /** |
| * True if this token is a keyword or an identifier. |
| */ |
| bool get isKeywordOrIdentifier; |
| |
| /** |
| * Return `true` if this token is a modifier such as `abstract` or `const`. |
| */ |
| bool get isModifier; |
| |
| /** |
| * Return `true` if this token represents an operator. |
| */ |
| bool get isOperator; |
| |
| /** |
| * Return `true` if this token is a synthetic token. A synthetic token is a |
| * token that was introduced by the parser in order to recover from an error |
| * in the code. |
| */ |
| bool get isSynthetic; |
| |
| /** |
| * Return `true` if this token is a keyword starting a top level declaration |
| * such as `class`, `enum`, `import`, etc. |
| */ |
| bool get isTopLevelKeyword; |
| |
| /** |
| * Return `true` if this token represents an operator that can be defined by |
| * users. |
| */ |
| bool get isUserDefinableOperator; |
| |
| /** |
| * Return the keyword, if a keyword token, or `null` otherwise. |
| */ |
| Keyword? get keyword; |
| |
| /** |
| * The kind enum of this token as determined by its [type]. |
| */ |
| int get kind; |
| |
| @override |
| int get length; |
| |
| /** |
| * Return the lexeme that represents this token. |
| * |
| * For [StringToken]s the [lexeme] includes the quotes, explicit escapes, etc. |
| */ |
| String get lexeme; |
| |
| /** |
| * Return the next token in the token stream. |
| */ |
| Token? get next; |
| |
| /** |
| * Return the next token in the token stream. |
| */ |
| void set next(Token? next); |
| |
| @override |
| int get offset; |
| |
| /** |
| * Set the offset from the beginning of the file to the first character in |
| * the token to the given [offset]. |
| */ |
| void set offset(int offset); |
| |
| /** |
| * Return the first comment in the list of comments that precede this token, |
| * or `null` if there are no comments preceding this token. Additional |
| * comments can be reached by following the token stream using [next] until |
| * `null` is returned. |
| * |
| * For example, if the original contents were `/* one */ /* two */ id`, then |
| * the first preceding comment token will have a lexeme of `/* one */` and |
| * the next comment token will have a lexeme of `/* two */`. |
| */ |
| CommentToken? get precedingComments; |
| |
| /** |
| * Return the previous token in the token stream. |
| */ |
| Token? get previous; |
| |
| /** |
| * Set the previous token in the token stream to the given [token]. |
| */ |
| void set previous(Token? token); |
| |
| /** |
| * For symbol and keyword tokens, returns the string value represented by this |
| * token. For [StringToken]s this method returns [:null:]. |
| * |
| * For [SymbolToken]s and [KeywordToken]s, the string value is a compile-time |
| * constant originating in the [TokenType] or in the [Keyword] instance. |
| * This allows testing for keywords and symbols using [:identical:], e.g., |
| * [:identical('class', token.value):]. |
| * |
| * Note that returning [:null:] for string tokens is important to identify |
| * symbols and keywords, we cannot use [lexeme] instead. The string literal |
| * "$a($b" |
| * produces ..., SymbolToken($), StringToken(a), StringToken((), ... |
| * |
| * After parsing the identifier 'a', the parser tests for a function |
| * declaration using [:identical(next.stringValue, '('):], which (rightfully) |
| * returns false because stringValue returns [:null:]. |
| */ |
| String? get stringValue; |
| |
| /** |
| * Return the type of the token. |
| */ |
| TokenType get type; |
| |
| /** |
| * Return a newly created token that is a copy of this tokens |
| * including any [preceedingComment] tokens, |
| * but that is not a part of any token stream. |
| */ |
| Token copy(); |
| |
| /** |
| * Copy a linked list of comment tokens identical to the given comment tokens. |
| */ |
| CommentToken? copyComments(CommentToken? token); |
| |
| /** |
| * Return `true` if this token has any one of the given [types]. |
| */ |
| bool matchesAny(List<TokenType> types); |
| |
| /** |
| * Set the next token in the token stream to the given [token]. This has the |
| * side-effect of setting this token to be the previous token for the given |
| * token. Return the token that was passed in. |
| */ |
| Token setNext(Token token); |
| |
| /** |
| * Set the next token in the token stream to the given token without changing |
| * which token is the previous token for the given token. Return the token |
| * that was passed in. |
| */ |
| Token? setNextWithoutSettingPrevious(Token? token); |
| |
| /** |
| * Returns a textual representation of this token to be used for debugging |
| * purposes. The resulting string might contain information about the |
| * structure of the token, for example 'StringToken(foo)' for the identifier |
| * token 'foo'. |
| * |
| * Use [lexeme] for the text actually parsed by the token. |
| */ |
| @override |
| String toString(); |
| |
| /** |
| * Return the value of this token. For keyword tokens, this is the keyword |
| * associated with the token, for other tokens it is the lexeme associated |
| * with the token. |
| */ |
| Object value(); |
| |
| /** |
| * Compare the given tokens to find the token that appears first in the |
| * source being parsed. That is, return the left-most of all of the tokens. |
| * Return the token with the smallest offset, or `null` if all of the |
| * tokens are `null`. |
| */ |
| static Token? lexicallyFirst([Token? t1, Token? t2, Token? t3, Token? t4]) { |
| Token? result = t1; |
| if (result == null || t2 != null && t2.offset < result.offset) { |
| result = t2; |
| } |
| if (result == null || t3 != null && t3.offset < result.offset) { |
| result = t3; |
| } |
| if (result == null || t4 != null && t4.offset < result.offset) { |
| result = t4; |
| } |
| return result; |
| } |
| } |
| |
| /** |
| * The classes (or groups) of tokens with a similar use. |
| */ |
| class TokenClass { |
| /** |
| * A value used to indicate that the token type is not part of any specific |
| * class of token. |
| */ |
| static const TokenClass NO_CLASS = const TokenClass('NO_CLASS'); |
| |
| /** |
| * A value used to indicate that the token type is an additive operator. |
| */ |
| static const TokenClass ADDITIVE_OPERATOR = |
| const TokenClass('ADDITIVE_OPERATOR', ADDITIVE_PRECEDENCE); |
| |
| /** |
| * A value used to indicate that the token type is an assignment operator. |
| */ |
| static const TokenClass ASSIGNMENT_OPERATOR = |
| const TokenClass('ASSIGNMENT_OPERATOR', ASSIGNMENT_PRECEDENCE); |
| |
| /** |
| * A value used to indicate that the token type is a bitwise-and operator. |
| */ |
| static const TokenClass BITWISE_AND_OPERATOR = |
| const TokenClass('BITWISE_AND_OPERATOR', BITWISE_AND_PRECEDENCE); |
| |
| /** |
| * A value used to indicate that the token type is a bitwise-or operator. |
| */ |
| static const TokenClass BITWISE_OR_OPERATOR = |
| const TokenClass('BITWISE_OR_OPERATOR', BITWISE_OR_PRECEDENCE); |
| |
| /** |
| * A value used to indicate that the token type is a bitwise-xor operator. |
| */ |
| static const TokenClass BITWISE_XOR_OPERATOR = |
| const TokenClass('BITWISE_XOR_OPERATOR', BITWISE_XOR_PRECEDENCE); |
| |
| /** |
| * A value used to indicate that the token type is a cascade operator. |
| */ |
| static const TokenClass CASCADE_OPERATOR = |
| const TokenClass('CASCADE_OPERATOR', CASCADE_PRECEDENCE); |
| |
| /** |
| * A value used to indicate that the token type is a conditional operator. |
| */ |
| static const TokenClass CONDITIONAL_OPERATOR = |
| const TokenClass('CONDITIONAL_OPERATOR', CONDITIONAL_PRECEDENCE); |
| |
| /** |
| * A value used to indicate that the token type is an equality operator. |
| */ |
| static const TokenClass EQUALITY_OPERATOR = |
| const TokenClass('EQUALITY_OPERATOR', EQUALITY_PRECEDENCE); |
| |
| /** |
| * A value used to indicate that the token type is an if-null operator. |
| */ |
| static const TokenClass IF_NULL_OPERATOR = |
| const TokenClass('IF_NULL_OPERATOR', IF_NULL_PRECEDENCE); |
| |
| /** |
| * A value used to indicate that the token type is a logical-and operator. |
| */ |
| static const TokenClass LOGICAL_AND_OPERATOR = |
| const TokenClass('LOGICAL_AND_OPERATOR', LOGICAL_AND_PRECEDENCE); |
| |
| /** |
| * A value used to indicate that the token type is a logical-or operator. |
| */ |
| static const TokenClass LOGICAL_OR_OPERATOR = |
| const TokenClass('LOGICAL_OR_OPERATOR', LOGICAL_OR_PRECEDENCE); |
| |
| /** |
| * A value used to indicate that the token type is a multiplicative operator. |
| */ |
| static const TokenClass MULTIPLICATIVE_OPERATOR = |
| const TokenClass('MULTIPLICATIVE_OPERATOR', MULTIPLICATIVE_PRECEDENCE); |
| |
| /** |
| * A value used to indicate that the token type is a relational operator. |
| */ |
| static const TokenClass RELATIONAL_OPERATOR = |
| const TokenClass('RELATIONAL_OPERATOR', RELATIONAL_PRECEDENCE); |
| |
| /** |
| * A value used to indicate that the token type is a shift operator. |
| */ |
| static const TokenClass SHIFT_OPERATOR = |
| const TokenClass('SHIFT_OPERATOR', SHIFT_PRECEDENCE); |
| |
| /** |
| * A value used to indicate that the token type is a unary operator. |
| */ |
| static const TokenClass UNARY_POSTFIX_OPERATOR = |
| const TokenClass('UNARY_POSTFIX_OPERATOR', POSTFIX_PRECEDENCE); |
| |
| /** |
| * A value used to indicate that the token type is a unary operator. |
| */ |
| static const TokenClass UNARY_PREFIX_OPERATOR = |
| const TokenClass('UNARY_PREFIX_OPERATOR', PREFIX_PRECEDENCE); |
| |
| /** |
| * The name of the token class. |
| */ |
| final String name; |
| |
| /** |
| * The precedence of tokens of this class, or `0` if the such tokens do not |
| * represent an operator. |
| */ |
| final int precedence; |
| |
| /** |
| * Initialize a newly created class of tokens to have the given [name] and |
| * [precedence]. |
| */ |
| const TokenClass(this.name, [this.precedence = NO_PRECEDENCE]); |
| |
| @override |
| String toString() => name; |
| } |
| |
| /** |
| * The types of tokens that can be returned by the scanner. |
| * |
| * Clients may not extend, implement or mix-in this class. |
| */ |
| class TokenType { |
| /** |
| * The type of the token that marks the start or end of the input. |
| */ |
| static const TokenType EOF = |
| const TokenType('', 'EOF', NO_PRECEDENCE, EOF_TOKEN); |
| |
| static const TokenType DOUBLE = const TokenType( |
| 'double', 'DOUBLE', NO_PRECEDENCE, DOUBLE_TOKEN, |
| stringValue: null); |
| |
| static const TokenType HEXADECIMAL = const TokenType( |
| 'hexadecimal', 'HEXADECIMAL', NO_PRECEDENCE, HEXADECIMAL_TOKEN, |
| stringValue: null); |
| |
| static const TokenType IDENTIFIER = const TokenType( |
| 'identifier', 'IDENTIFIER', NO_PRECEDENCE, IDENTIFIER_TOKEN, |
| stringValue: null); |
| |
| static const TokenType INT = const TokenType( |
| 'int', 'INT', NO_PRECEDENCE, INT_TOKEN, |
| stringValue: null); |
| |
| static const TokenType MULTI_LINE_COMMENT = const TokenType( |
| 'comment', 'MULTI_LINE_COMMENT', NO_PRECEDENCE, COMMENT_TOKEN, |
| stringValue: null); |
| |
| static const TokenType SCRIPT_TAG = |
| const TokenType('script', 'SCRIPT_TAG', NO_PRECEDENCE, SCRIPT_TOKEN); |
| |
| static const TokenType SINGLE_LINE_COMMENT = const TokenType( |
| 'comment', 'SINGLE_LINE_COMMENT', NO_PRECEDENCE, COMMENT_TOKEN, |
| stringValue: null); |
| |
| static const TokenType STRING = const TokenType( |
| 'string', 'STRING', NO_PRECEDENCE, STRING_TOKEN, |
| stringValue: null); |
| |
| static const TokenType AMPERSAND = const TokenType( |
| '&', 'AMPERSAND', BITWISE_AND_PRECEDENCE, AMPERSAND_TOKEN, |
| isOperator: true, isBinaryOperator: true, isUserDefinableOperator: true); |
| |
| static const TokenType AMPERSAND_AMPERSAND = const TokenType('&&', |
| 'AMPERSAND_AMPERSAND', LOGICAL_AND_PRECEDENCE, AMPERSAND_AMPERSAND_TOKEN, |
| isOperator: true, isBinaryOperator: true); |
| |
| // This is not yet part of the language and not supported by fasta |
| static const TokenType AMPERSAND_AMPERSAND_EQ = const TokenType( |
| '&&=', |
| 'AMPERSAND_AMPERSAND_EQ', |
| ASSIGNMENT_PRECEDENCE, |
| AMPERSAND_AMPERSAND_EQ_TOKEN, |
| binaryOperatorOfCompoundAssignment: TokenType.AMPERSAND_AMPERSAND, |
| isOperator: true); |
| |
| static const TokenType AMPERSAND_EQ = const TokenType( |
| '&=', 'AMPERSAND_EQ', ASSIGNMENT_PRECEDENCE, AMPERSAND_EQ_TOKEN, |
| binaryOperatorOfCompoundAssignment: TokenType.AMPERSAND, |
| isOperator: true); |
| |
| static const TokenType AT = |
| const TokenType('@', 'AT', NO_PRECEDENCE, AT_TOKEN); |
| |
| static const TokenType BANG = const TokenType( |
| '!', 'BANG', PREFIX_PRECEDENCE, BANG_TOKEN, |
| isOperator: true); |
| |
| static const TokenType BANG_EQ = const TokenType( |
| '!=', 'BANG_EQ', EQUALITY_PRECEDENCE, BANG_EQ_TOKEN, |
| isOperator: true); |
| |
| static const TokenType BANG_EQ_EQ = const TokenType( |
| '!==', 'BANG_EQ_EQ', EQUALITY_PRECEDENCE, BANG_EQ_EQ_TOKEN); |
| |
| static const TokenType BAR = const TokenType( |
| '|', 'BAR', BITWISE_OR_PRECEDENCE, BAR_TOKEN, |
| isOperator: true, isBinaryOperator: true, isUserDefinableOperator: true); |
| |
| static const TokenType BAR_BAR = const TokenType( |
| '||', 'BAR_BAR', LOGICAL_OR_PRECEDENCE, BAR_BAR_TOKEN, |
| isOperator: true, isBinaryOperator: true); |
| |
| // This is not yet part of the language and not supported by fasta |
| static const TokenType BAR_BAR_EQ = const TokenType( |
| '||=', 'BAR_BAR_EQ', ASSIGNMENT_PRECEDENCE, BAR_BAR_EQ_TOKEN, |
| binaryOperatorOfCompoundAssignment: TokenType.BAR_BAR, isOperator: true); |
| |
| static const TokenType BAR_EQ = const TokenType( |
| '|=', 'BAR_EQ', ASSIGNMENT_PRECEDENCE, BAR_EQ_TOKEN, |
| binaryOperatorOfCompoundAssignment: TokenType.BAR, isOperator: true); |
| |
| static const TokenType COLON = |
| const TokenType(':', 'COLON', NO_PRECEDENCE, COLON_TOKEN); |
| |
| static const TokenType COMMA = |
| const TokenType(',', 'COMMA', NO_PRECEDENCE, COMMA_TOKEN); |
| |
| static const TokenType CARET = const TokenType( |
| '^', 'CARET', BITWISE_XOR_PRECEDENCE, CARET_TOKEN, |
| isOperator: true, isBinaryOperator: true, isUserDefinableOperator: true); |
| |
| static const TokenType CARET_EQ = const TokenType( |
| '^=', 'CARET_EQ', ASSIGNMENT_PRECEDENCE, CARET_EQ_TOKEN, |
| binaryOperatorOfCompoundAssignment: TokenType.CARET, isOperator: true); |
| |
| static const TokenType CLOSE_CURLY_BRACKET = const TokenType( |
| '}', 'CLOSE_CURLY_BRACKET', NO_PRECEDENCE, CLOSE_CURLY_BRACKET_TOKEN); |
| |
| static const TokenType CLOSE_PAREN = |
| const TokenType(')', 'CLOSE_PAREN', NO_PRECEDENCE, CLOSE_PAREN_TOKEN); |
| |
| static const TokenType CLOSE_SQUARE_BRACKET = const TokenType( |
| ']', 'CLOSE_SQUARE_BRACKET', NO_PRECEDENCE, CLOSE_SQUARE_BRACKET_TOKEN); |
| |
| static const TokenType EQ = const TokenType( |
| '=', 'EQ', ASSIGNMENT_PRECEDENCE, EQ_TOKEN, |
| isOperator: true); |
| |
| static const TokenType EQ_EQ = const TokenType( |
| '==', 'EQ_EQ', EQUALITY_PRECEDENCE, EQ_EQ_TOKEN, |
| isOperator: true, isBinaryOperator: true, isUserDefinableOperator: true); |
| |
| /// The `===` operator is not supported in the Dart language |
| /// but is parsed as such by the scanner to support better recovery |
| /// when a JavaScript code snippet is pasted into a Dart file. |
| static const TokenType EQ_EQ_EQ = |
| const TokenType('===', 'EQ_EQ_EQ', EQUALITY_PRECEDENCE, EQ_EQ_EQ_TOKEN); |
| |
| static const TokenType FUNCTION = |
| const TokenType('=>', 'FUNCTION', NO_PRECEDENCE, FUNCTION_TOKEN); |
| |
| static const TokenType GT = const TokenType( |
| '>', 'GT', RELATIONAL_PRECEDENCE, GT_TOKEN, |
| isOperator: true, isBinaryOperator: true, isUserDefinableOperator: true); |
| |
| static const TokenType GT_EQ = const TokenType( |
| '>=', 'GT_EQ', RELATIONAL_PRECEDENCE, GT_EQ_TOKEN, |
| isOperator: true, isBinaryOperator: true, isUserDefinableOperator: true); |
| |
| static const TokenType GT_GT = const TokenType( |
| '>>', 'GT_GT', SHIFT_PRECEDENCE, GT_GT_TOKEN, |
| isOperator: true, isBinaryOperator: true, isUserDefinableOperator: true); |
| |
| static const TokenType GT_GT_EQ = const TokenType( |
| '>>=', 'GT_GT_EQ', ASSIGNMENT_PRECEDENCE, GT_GT_EQ_TOKEN, |
| binaryOperatorOfCompoundAssignment: TokenType.GT_GT, isOperator: true); |
| |
| static const TokenType GT_GT_GT = const TokenType( |
| '>>>', 'GT_GT_GT', SHIFT_PRECEDENCE, GT_GT_GT_TOKEN, |
| isOperator: true, isBinaryOperator: true, isUserDefinableOperator: true); |
| |
| static const TokenType GT_GT_GT_EQ = const TokenType( |
| '>>>=', 'GT_GT_GT_EQ', ASSIGNMENT_PRECEDENCE, GT_GT_GT_EQ_TOKEN, |
| binaryOperatorOfCompoundAssignment: TokenType.GT_GT_GT, isOperator: true); |
| |
| static const TokenType HASH = |
| const TokenType('#', 'HASH', NO_PRECEDENCE, HASH_TOKEN); |
| |
| static const TokenType INDEX = const TokenType( |
| '[]', 'INDEX', SELECTOR_PRECEDENCE, INDEX_TOKEN, |
| isOperator: true, isUserDefinableOperator: true); |
| |
| static const TokenType INDEX_EQ = const TokenType( |
| '[]=', 'INDEX_EQ', NO_PRECEDENCE, INDEX_EQ_TOKEN, |
| isOperator: true, isUserDefinableOperator: true); |
| |
| static const TokenType LT = const TokenType( |
| '<', 'LT', RELATIONAL_PRECEDENCE, LT_TOKEN, |
| isOperator: true, isBinaryOperator: true, isUserDefinableOperator: true); |
| |
| static const TokenType LT_EQ = const TokenType( |
| '<=', 'LT_EQ', RELATIONAL_PRECEDENCE, LT_EQ_TOKEN, |
| isOperator: true, isBinaryOperator: true, isUserDefinableOperator: true); |
| |
| static const TokenType LT_LT = const TokenType( |
| '<<', 'LT_LT', SHIFT_PRECEDENCE, LT_LT_TOKEN, |
| isOperator: true, isBinaryOperator: true, isUserDefinableOperator: true); |
| |
| static const TokenType LT_LT_EQ = const TokenType( |
| '<<=', 'LT_LT_EQ', ASSIGNMENT_PRECEDENCE, LT_LT_EQ_TOKEN, |
| binaryOperatorOfCompoundAssignment: TokenType.LT_LT, isOperator: true); |
| |
| static const TokenType MINUS = const TokenType( |
| '-', 'MINUS', ADDITIVE_PRECEDENCE, MINUS_TOKEN, |
| isOperator: true, isBinaryOperator: true, isUserDefinableOperator: true); |
| |
| static const TokenType MINUS_EQ = const TokenType( |
| '-=', 'MINUS_EQ', ASSIGNMENT_PRECEDENCE, MINUS_EQ_TOKEN, |
| binaryOperatorOfCompoundAssignment: TokenType.MINUS, isOperator: true); |
| |
| static const TokenType MINUS_MINUS = const TokenType( |
| '--', 'MINUS_MINUS', POSTFIX_PRECEDENCE, MINUS_MINUS_TOKEN, |
| isOperator: true); |
| |
| static const TokenType OPEN_CURLY_BRACKET = const TokenType( |
| '{', 'OPEN_CURLY_BRACKET', NO_PRECEDENCE, OPEN_CURLY_BRACKET_TOKEN); |
| |
| static const TokenType OPEN_PAREN = |
| const TokenType('(', 'OPEN_PAREN', SELECTOR_PRECEDENCE, OPEN_PAREN_TOKEN); |
| |
| static const TokenType OPEN_SQUARE_BRACKET = const TokenType('[', |
| 'OPEN_SQUARE_BRACKET', SELECTOR_PRECEDENCE, OPEN_SQUARE_BRACKET_TOKEN); |
| |
| static const TokenType PERCENT = const TokenType( |
| '%', 'PERCENT', MULTIPLICATIVE_PRECEDENCE, PERCENT_TOKEN, |
| isOperator: true, isBinaryOperator: true, isUserDefinableOperator: true); |
| |
| static const TokenType PERCENT_EQ = const TokenType( |
| '%=', 'PERCENT_EQ', ASSIGNMENT_PRECEDENCE, PERCENT_EQ_TOKEN, |
| binaryOperatorOfCompoundAssignment: TokenType.PERCENT, isOperator: true); |
| |
| static const TokenType PERIOD = |
| const TokenType('.', 'PERIOD', SELECTOR_PRECEDENCE, PERIOD_TOKEN); |
| |
| static const TokenType PERIOD_PERIOD = const TokenType( |
| '..', 'PERIOD_PERIOD', CASCADE_PRECEDENCE, PERIOD_PERIOD_TOKEN, |
| isOperator: true); |
| |
| static const TokenType PLUS = const TokenType( |
| '+', 'PLUS', ADDITIVE_PRECEDENCE, PLUS_TOKEN, |
| isOperator: true, isBinaryOperator: true, isUserDefinableOperator: true); |
| |
| static const TokenType PLUS_EQ = const TokenType( |
| '+=', 'PLUS_EQ', ASSIGNMENT_PRECEDENCE, PLUS_EQ_TOKEN, |
| binaryOperatorOfCompoundAssignment: TokenType.PLUS, isOperator: true); |
| |
| static const TokenType PLUS_PLUS = const TokenType( |
| '++', 'PLUS_PLUS', POSTFIX_PRECEDENCE, PLUS_PLUS_TOKEN, |
| isOperator: true); |
| |
| static const TokenType QUESTION = const TokenType( |
| '?', 'QUESTION', CONDITIONAL_PRECEDENCE, QUESTION_TOKEN, |
| isOperator: true); |
| |
| static const TokenType QUESTION_PERIOD = const TokenType( |
| '?.', 'QUESTION_PERIOD', SELECTOR_PRECEDENCE, QUESTION_PERIOD_TOKEN, |
| isOperator: true); |
| |
| static const TokenType QUESTION_QUESTION = const TokenType( |
| '??', 'QUESTION_QUESTION', IF_NULL_PRECEDENCE, QUESTION_QUESTION_TOKEN, |
| isOperator: true, isBinaryOperator: true); |
| |
| static const TokenType QUESTION_QUESTION_EQ = const TokenType('??=', |
| 'QUESTION_QUESTION_EQ', ASSIGNMENT_PRECEDENCE, QUESTION_QUESTION_EQ_TOKEN, |
| binaryOperatorOfCompoundAssignment: TokenType.QUESTION_QUESTION, |
| isOperator: true); |
| |
| static const TokenType SEMICOLON = |
| const TokenType(';', 'SEMICOLON', NO_PRECEDENCE, SEMICOLON_TOKEN); |
| |
| static const TokenType SLASH = const TokenType( |
| '/', 'SLASH', MULTIPLICATIVE_PRECEDENCE, SLASH_TOKEN, |
| isOperator: true, isBinaryOperator: true, isUserDefinableOperator: true); |
| |
| static const TokenType SLASH_EQ = const TokenType( |
| '/=', 'SLASH_EQ', ASSIGNMENT_PRECEDENCE, SLASH_EQ_TOKEN, |
| binaryOperatorOfCompoundAssignment: TokenType.SLASH, isOperator: true); |
| |
| static const TokenType STAR = const TokenType( |
| '*', 'STAR', MULTIPLICATIVE_PRECEDENCE, STAR_TOKEN, |
| isOperator: true, isBinaryOperator: true, isUserDefinableOperator: true); |
| |
| static const TokenType STAR_EQ = const TokenType( |
| '*=', 'STAR_EQ', ASSIGNMENT_PRECEDENCE, STAR_EQ_TOKEN, |
| binaryOperatorOfCompoundAssignment: TokenType.STAR, isOperator: true); |
| |
| static const TokenType STRING_INTERPOLATION_EXPRESSION = const TokenType( |
| '\${', |
| 'STRING_INTERPOLATION_EXPRESSION', |
| NO_PRECEDENCE, |
| STRING_INTERPOLATION_TOKEN); |
| |
| static const TokenType STRING_INTERPOLATION_IDENTIFIER = const TokenType( |
| '\$', |
| 'STRING_INTERPOLATION_IDENTIFIER', |
| NO_PRECEDENCE, |
| STRING_INTERPOLATION_IDENTIFIER_TOKEN); |
| |
| static const TokenType TILDE = const TokenType( |
| '~', 'TILDE', PREFIX_PRECEDENCE, TILDE_TOKEN, |
| isOperator: true, isUserDefinableOperator: true); |
| |
| static const TokenType TILDE_SLASH = const TokenType( |
| '~/', 'TILDE_SLASH', MULTIPLICATIVE_PRECEDENCE, TILDE_SLASH_TOKEN, |
| isOperator: true, isBinaryOperator: true, isUserDefinableOperator: true); |
| |
| static const TokenType TILDE_SLASH_EQ = const TokenType( |
| '~/=', 'TILDE_SLASH_EQ', ASSIGNMENT_PRECEDENCE, TILDE_SLASH_EQ_TOKEN, |
| binaryOperatorOfCompoundAssignment: TokenType.TILDE_SLASH, |
| isOperator: true); |
| |
| static const TokenType BACKPING = |
| const TokenType('`', 'BACKPING', NO_PRECEDENCE, BACKPING_TOKEN); |
| |
| static const TokenType BACKSLASH = |
| const TokenType('\\', 'BACKSLASH', NO_PRECEDENCE, BACKSLASH_TOKEN); |
| |
| static const TokenType PERIOD_PERIOD_PERIOD = const TokenType( |
| '...', 'PERIOD_PERIOD_PERIOD', NO_PRECEDENCE, PERIOD_PERIOD_PERIOD_TOKEN); |
| |
| static const TokenType PERIOD_PERIOD_PERIOD_QUESTION = const TokenType( |
| '...?', |
| 'PERIOD_PERIOD_PERIOD_QUESTION', |
| NO_PRECEDENCE, |
| PERIOD_PERIOD_PERIOD_QUESTION_TOKEN); |
| |
| static const TokenType QUESTION_PERIOD_PERIOD = const TokenType( |
| '?..', |
| 'QUESTION_PERIOD_PERIOD', |
| CASCADE_PRECEDENCE, |
| QUESTION_PERIOD_PERIOD_TOKEN); |
| |
| static const TokenType AS = Keyword.AS; |
| |
| static const TokenType IS = Keyword.IS; |
| |
| /** |
| * Token type used by error tokens. |
| */ |
| static const TokenType BAD_INPUT = const TokenType( |
| 'malformed input', 'BAD_INPUT', NO_PRECEDENCE, BAD_INPUT_TOKEN, |
| stringValue: null); |
| |
| /** |
| * Token type used by synthetic tokens that are created during parser |
| * recovery (non-analyzer use case). |
| */ |
| static const TokenType RECOVERY = const TokenType( |
| 'recovery', 'RECOVERY', NO_PRECEDENCE, RECOVERY_TOKEN, |
| stringValue: null); |
| |
| // TODO(danrubel): "all" is misleading |
| // because this list does not include all TokenType instances. |
| static const List<TokenType> all = const <TokenType>[ |
| TokenType.EOF, |
| TokenType.DOUBLE, |
| TokenType.HEXADECIMAL, |
| TokenType.IDENTIFIER, |
| TokenType.INT, |
| TokenType.MULTI_LINE_COMMENT, |
| TokenType.SCRIPT_TAG, |
| TokenType.SINGLE_LINE_COMMENT, |
| TokenType.STRING, |
| TokenType.AMPERSAND, |
| TokenType.AMPERSAND_AMPERSAND, |
| TokenType.AMPERSAND_EQ, |
| TokenType.AT, |
| TokenType.BANG, |
| TokenType.BANG_EQ, |
| TokenType.BAR, |
| TokenType.BAR_BAR, |
| TokenType.BAR_EQ, |
| TokenType.COLON, |
| TokenType.COMMA, |
| TokenType.CARET, |
| TokenType.CARET_EQ, |
| TokenType.CLOSE_CURLY_BRACKET, |
| TokenType.CLOSE_PAREN, |
| TokenType.CLOSE_SQUARE_BRACKET, |
| TokenType.EQ, |
| TokenType.EQ_EQ, |
| TokenType.FUNCTION, |
| TokenType.GT, |
| TokenType.GT_EQ, |
| TokenType.GT_GT, |
| TokenType.GT_GT_EQ, |
| TokenType.HASH, |
| TokenType.INDEX, |
| TokenType.INDEX_EQ, |
| TokenType.LT, |
| TokenType.LT_EQ, |
| TokenType.LT_LT, |
| TokenType.LT_LT_EQ, |
| TokenType.MINUS, |
| TokenType.MINUS_EQ, |
| TokenType.MINUS_MINUS, |
| TokenType.OPEN_CURLY_BRACKET, |
| TokenType.OPEN_PAREN, |
| TokenType.OPEN_SQUARE_BRACKET, |
| TokenType.PERCENT, |
| TokenType.PERCENT_EQ, |
| TokenType.PERIOD, |
| TokenType.PERIOD_PERIOD, |
| TokenType.PLUS, |
| TokenType.PLUS_EQ, |
| TokenType.PLUS_PLUS, |
| TokenType.QUESTION, |
| TokenType.QUESTION_PERIOD, |
| TokenType.QUESTION_QUESTION, |
| TokenType.QUESTION_QUESTION_EQ, |
| TokenType.SEMICOLON, |
| TokenType.SLASH, |
| TokenType.SLASH_EQ, |
| TokenType.STAR, |
| TokenType.STAR_EQ, |
| TokenType.STRING_INTERPOLATION_EXPRESSION, |
| TokenType.STRING_INTERPOLATION_IDENTIFIER, |
| TokenType.TILDE, |
| TokenType.TILDE_SLASH, |
| TokenType.TILDE_SLASH_EQ, |
| TokenType.BACKPING, |
| TokenType.BACKSLASH, |
| TokenType.PERIOD_PERIOD_PERIOD, |
| TokenType.PERIOD_PERIOD_PERIOD_QUESTION, |
| |
| // TODO(danrubel): Should these be added to the "all" list? |
| //TokenType.IS, |
| //TokenType.AS, |
| |
| // These are not yet part of the language and not supported by fasta |
| //TokenType.AMPERSAND_AMPERSAND_EQ, |
| //TokenType.BAR_BAR_EQ, |
| |
| // Supported by fasta but not part of the language |
| //TokenType.BANG_EQ_EQ, |
| //TokenType.EQ_EQ_EQ, |
| |
| // Used by synthetic tokens generated during recovery |
| //TokenType.BAD_INPUT, |
| //TokenType.RECOVERY, |
| ]; |
| |
| /** |
| * The binary operator that is invoked by this compound assignment operator, |
| * or `null` otherwise. |
| */ |
| final TokenType? binaryOperatorOfCompoundAssignment; |
| |
| final int kind; |
| |
| /** |
| * `true` if this token type represents a modifier |
| * such as `abstract` or `const`. |
| */ |
| final bool isModifier; |
| |
| /** |
| * `true` if this token type represents an operator. |
| */ |
| final bool isOperator; |
| |
| /** |
| * `true` if this token type represents a binary operator. |
| */ |
| final bool isBinaryOperator; |
| |
| /** |
| * `true` if this token type represents a keyword starting a top level |
| * declaration such as `class`, `enum`, `import`, etc. |
| */ |
| final bool isTopLevelKeyword; |
| |
| /** |
| * `true` if this token type represents an operator |
| * that can be defined by users. |
| */ |
| final bool isUserDefinableOperator; |
| |
| /** |
| * The lexeme that defines this type of token, |
| * or `null` if there is more than one possible lexeme for this type of token. |
| */ |
| final String lexeme; |
| |
| /** |
| * The name of the token type. |
| */ |
| final String name; |
| |
| /** |
| * The precedence of this type of token, |
| * or `0` if the token does not represent an operator. |
| */ |
| final int precedence; |
| |
| /** |
| * See [Token.stringValue] for an explanation. |
| */ |
| final String? stringValue; |
| |
| const TokenType(this.lexeme, this.name, this.precedence, this.kind, |
| {this.binaryOperatorOfCompoundAssignment, |
| this.isBinaryOperator: false, |
| this.isModifier: false, |
| this.isOperator: false, |
| this.isTopLevelKeyword: false, |
| this.isUserDefinableOperator: false, |
| String? stringValue: 'unspecified'}) |
| : this.stringValue = stringValue == 'unspecified' ? lexeme : stringValue; |
| |
| /** |
| * Return `true` if this type of token represents an additive operator. |
| */ |
| bool get isAdditiveOperator => precedence == ADDITIVE_PRECEDENCE; |
| |
| /** |
| * Return `true` if this type of token represents an assignment operator. |
| */ |
| bool get isAssignmentOperator => precedence == ASSIGNMENT_PRECEDENCE; |
| |
| /** |
| * Return `true` if this type of token represents an associative operator. An |
| * associative operator is an operator for which the following equality is |
| * true: `(a * b) * c == a * (b * c)`. In other words, if the result of |
| * applying the operator to multiple operands does not depend on the order in |
| * which those applications occur. |
| * |
| * Note: This method considers the logical-and and logical-or operators to be |
| * associative, even though the order in which the application of those |
| * operators can have an effect because evaluation of the right-hand operand |
| * is conditional. |
| */ |
| bool get isAssociativeOperator => |
| this == TokenType.AMPERSAND || |
| this == TokenType.AMPERSAND_AMPERSAND || |
| this == TokenType.BAR || |
| this == TokenType.BAR_BAR || |
| this == TokenType.CARET || |
| this == TokenType.PLUS || |
| this == TokenType.STAR; |
| |
| /** |
| * A flag indicating whether the keyword is a "built-in" identifier. |
| */ |
| bool get isBuiltIn => false; |
| |
| /// A flag indicating whether the keyword is a "reserved word". |
| bool get isReservedWord => false; |
| |
| /** |
| * Return `true` if this type of token represents an equality operator. |
| */ |
| bool get isEqualityOperator => |
| this == TokenType.BANG_EQ || this == TokenType.EQ_EQ; |
| |
| /** |
| * Return `true` if this type of token represents an increment operator. |
| */ |
| bool get isIncrementOperator => |
| this == TokenType.PLUS_PLUS || this == TokenType.MINUS_MINUS; |
| |
| /** |
| * Return `true` if this type of token is a keyword. |
| */ |
| bool get isKeyword => kind == KEYWORD_TOKEN; |
| |
| /** |
| * A flag indicating whether the keyword can be used as an identifier |
| * in some situations. |
| */ |
| bool get isPseudo => false; |
| |
| /** |
| * Return `true` if this type of token represents a multiplicative operator. |
| */ |
| bool get isMultiplicativeOperator => precedence == MULTIPLICATIVE_PRECEDENCE; |
| |
| /** |
| * Return `true` if this type of token represents a relational operator. |
| */ |
| bool get isRelationalOperator => |
| this == TokenType.LT || |
| this == TokenType.LT_EQ || |
| this == TokenType.GT || |
| this == TokenType.GT_EQ; |
| |
| /** |
| * Return `true` if this type of token represents a shift operator. |
| */ |
| bool get isShiftOperator => precedence == SHIFT_PRECEDENCE; |
| |
| /** |
| * Return `true` if this type of token represents a unary postfix operator. |
| */ |
| bool get isUnaryPostfixOperator => precedence == POSTFIX_PRECEDENCE; |
| |
| /** |
| * Return `true` if this type of token represents a unary prefix operator. |
| */ |
| bool get isUnaryPrefixOperator => |
| precedence == PREFIX_PRECEDENCE || |
| this == TokenType.MINUS || |
| this == TokenType.PLUS_PLUS || |
| this == TokenType.MINUS_MINUS; |
| |
| /** |
| * Return `true` if this type of token represents a selector operator |
| * (starting token of a selector). |
| */ |
| bool get isSelectorOperator => precedence == SELECTOR_PRECEDENCE; |
| |
| @override |
| String toString() => name; |
| } |
