/src/grammar.coffee
CoffeeScript | 963 lines | 678 code | 118 blank | 167 comment | 22 complexity | 27a38b3ee8e956b727f2abd4f0a90d7d MD5 | raw file
1# The CoffeeScript parser is generated by [Jison](https://github.com/zaach/jison) 2# from this grammar file. Jison is a bottom-up parser generator, similar in 3# style to [Bison](http://www.gnu.org/software/bison), implemented in JavaScript. 4# It can recognize [LALR(1), LR(0), SLR(1), and LR(1)](https://en.wikipedia.org/wiki/LR_grammar) 5# type grammars. To create the Jison parser, we list the pattern to match 6# on the left-hand side, and the action to take (usually the creation of syntax 7# tree nodes) on the right. As the parser runs, it 8# shifts tokens from our token stream, from left to right, and 9# [attempts to match](https://en.wikipedia.org/wiki/Bottom-up_parsing) 10# the token sequence against the rules below. When a match can be made, it 11# reduces into the [nonterminal](https://en.wikipedia.org/wiki/Terminal_and_nonterminal_symbols) 12# (the enclosing name at the top), and we proceed from there. 13# 14# If you run the `cake build:parser` command, Jison constructs a parse table 15# from our rules and saves it into `lib/parser.js`. 16 17# The only dependency is on the **Jison.Parser**. 18{Parser} = require 'jison' 19 20# Jison DSL 21# --------- 22 23# Since we're going to be wrapped in a function by Jison in any case, if our 24# action immediately returns a value, we can optimize by removing the function 25# wrapper and just returning the value directly. 26unwrap = /^function\s*\(\)\s*\{\s*return\s*([\s\S]*);\s*\}/ 27 28# Our handy DSL for Jison grammar generation, thanks to 29# [Tim Caswell](https://github.com/creationix). For every rule in the grammar, 30# we pass the pattern-defining string, the action to run, and extra options, 31# optionally. If no action is specified, we simply pass the value of the 32# previous nonterminal. 33o = (patternString, action, options) -> 34 patternString = patternString.replace /\s{2,}/g, ' ' 35 patternCount = patternString.split(' ').length 36 if action 37 action = if match = unwrap.exec action then match[1] else "(#{action}())" 38 39 # All runtime functions we need are defined on `yy` 40 action = action.replace /\bnew /g, '$&yy.' 41 action = action.replace /\b(?:Block\.wrap|extend)\b/g, 'yy.$&' 42 43 # Returns strings of functions to add to `parser.js` which add extra data 44 # that nodes may have, such as comments or location data. Location data 45 # is added to the first parameter passed in, and the parameter is returned. 46 # If the parameter is not a node, it will just be passed through unaffected. 47 getAddDataToNodeFunctionString = (first, last, forceUpdateLocation = yes) -> 48 "yy.addDataToNode(yy, @#{first}, #{if first[0] is '$' then '$$' else '$'}#{first}, #{if last then "@#{last}, #{if last[0] is '$' then '$$' else '$'}#{last}" else 'null, null'}, #{if forceUpdateLocation then 'true' else 'false'})" 49 50 returnsLoc = /^LOC/.test action 51 action = action.replace /LOC\(([0-9]*)\)/g, getAddDataToNodeFunctionString('$1') 52 action = action.replace /LOC\(([0-9]*),\s*([0-9]*)\)/g, getAddDataToNodeFunctionString('$1', '$2') 53 performActionFunctionString = "$$ = #{getAddDataToNodeFunctionString(1, patternCount, not returnsLoc)}(#{action});" 54 else 55 performActionFunctionString = '$$ = $1;' 56 57 [patternString, performActionFunctionString, options] 58 59# Grammatical Rules 60# ----------------- 61 62# In all of the rules that follow, you'll see the name of the nonterminal as 63# the key to a list of alternative matches. With each match's action, the 64# dollar-sign variables are provided by Jison as references to the value of 65# their numeric position, so in this rule: 66# 67# 'Expression UNLESS Expression' 68# 69# `$1` would be the value of the first `Expression`, `$2` would be the token 70# for the `UNLESS` terminal, and `$3` would be the value of the second 71# `Expression`. 72grammar = 73 74 # The **Root** is the top-level node in the syntax tree. Since we parse bottom-up, 75 # all parsing must end here. 76 Root: [ 77 o '', -> new Root new Block 78 o 'Body', -> new Root $1 79 ] 80 81 # Any list of statements and expressions, separated by line breaks or semicolons. 82 Body: [ 83 o 'Line', -> Block.wrap [$1] 84 o 'Body TERMINATOR Line', -> $1.push $3 85 o 'Body TERMINATOR' 86 ] 87 88 # Block and statements, which make up a line in a body. YieldReturn is a 89 # statement, but not included in Statement because that results in an ambiguous 90 # grammar. 91 Line: [ 92 o 'Expression' 93 o 'ExpressionLine' 94 o 'Statement' 95 o 'FuncDirective' 96 ] 97 98 FuncDirective: [ 99 o 'YieldReturn' 100 o 'AwaitReturn' 101 ] 102 103 # Pure statements which cannot be expressions. 104 Statement: [ 105 o 'Return' 106 o 'STATEMENT', -> new StatementLiteral $1 107 o 'Import' 108 o 'Export' 109 ] 110 111 # All the different types of expressions in our language. The basic unit of 112 # CoffeeScript is the **Expression** -- everything that can be an expression 113 # is one. Blocks serve as the building blocks of many other rules, making 114 # them somewhat circular. 115 Expression: [ 116 o 'Value' 117 o 'Code' 118 o 'Operation' 119 o 'Assign' 120 o 'If' 121 o 'Try' 122 o 'While' 123 o 'For' 124 o 'Switch' 125 o 'Class' 126 o 'Throw' 127 o 'Yield' 128 ] 129 130 # Expressions which are written in single line and would otherwise require being 131 # wrapped in braces: E.g `a = b if do -> f a is 1`, `if f (a) -> a*2 then ...`, 132 # `for x in do (obj) -> f obj when x > 8 then f x` 133 ExpressionLine: [ 134 o 'CodeLine' 135 o 'IfLine' 136 o 'OperationLine' 137 ] 138 139 Yield: [ 140 o 'YIELD', -> new Op $1, new Value new Literal '' 141 o 'YIELD Expression', -> new Op $1, $2 142 o 'YIELD INDENT Object OUTDENT', -> new Op $1, $3 143 o 'YIELD FROM Expression', -> new Op $1.concat($2), $3 144 ] 145 146 # An indented block of expressions. Note that the [Rewriter](rewriter.html) 147 # will convert some postfix forms into blocks for us, by adjusting the 148 # token stream. 149 Block: [ 150 o 'INDENT OUTDENT', -> new Block 151 o 'INDENT Body OUTDENT', -> $2 152 ] 153 154 Identifier: [ 155 o 'IDENTIFIER', -> new IdentifierLiteral $1 156 o 'JSX_TAG', -> new JSXTag $1.toString(), 157 tagNameLocationData: $1.tagNameToken[2] 158 closingTagOpeningBracketLocationData: $1.closingTagOpeningBracketToken?[2] 159 closingTagSlashLocationData: $1.closingTagSlashToken?[2] 160 closingTagNameLocationData: $1.closingTagNameToken?[2] 161 closingTagClosingBracketLocationData: $1.closingTagClosingBracketToken?[2] 162 ] 163 164 Property: [ 165 o 'PROPERTY', -> new PropertyName $1.toString() 166 ] 167 168 # Alphanumerics are separated from the other **Literal** matchers because 169 # they can also serve as keys in object literals. 170 AlphaNumeric: [ 171 o 'NUMBER', -> new NumberLiteral $1.toString(), parsedValue: $1.parsedValue 172 o 'String' 173 ] 174 175 String: [ 176 o 'STRING', -> 177 new StringLiteral( 178 $1.slice 1, -1 # strip artificial quotes and unwrap to primitive string 179 quote: $1.quote 180 initialChunk: $1.initialChunk 181 finalChunk: $1.finalChunk 182 indent: $1.indent 183 double: $1.double 184 heregex: $1.heregex 185 ) 186 o 'STRING_START Interpolations STRING_END', -> new StringWithInterpolations Block.wrap($2), quote: $1.quote, startQuote: LOC(1)(new Literal $1.toString()) 187 ] 188 189 Interpolations: [ 190 o 'InterpolationChunk', -> [$1] 191 o 'Interpolations InterpolationChunk', -> $1.concat $2 192 ] 193 194 InterpolationChunk: [ 195 o 'INTERPOLATION_START Body INTERPOLATION_END', -> new Interpolation $2 196 o 'INTERPOLATION_START INDENT Body OUTDENT INTERPOLATION_END', -> new Interpolation $3 197 o 'INTERPOLATION_START INTERPOLATION_END', -> new Interpolation 198 o 'String', -> $1 199 ] 200 201 # The .toString() calls here and elsewhere are to convert `String` objects 202 # back to primitive strings now that we've retrieved stowaway extra properties 203 Regex: [ 204 o 'REGEX', -> new RegexLiteral $1.toString(), delimiter: $1.delimiter, heregexCommentTokens: $1.heregexCommentTokens 205 o 'REGEX_START Invocation REGEX_END', -> new RegexWithInterpolations $2, heregexCommentTokens: $3.heregexCommentTokens 206 ] 207 208 # All of our immediate values. Generally these can be passed straight 209 # through and printed to JavaScript. 210 Literal: [ 211 o 'AlphaNumeric' 212 o 'JS', -> new PassthroughLiteral $1.toString(), here: $1.here, generated: $1.generated 213 o 'Regex' 214 o 'UNDEFINED', -> new UndefinedLiteral $1 215 o 'NULL', -> new NullLiteral $1 216 o 'BOOL', -> new BooleanLiteral $1.toString(), originalValue: $1.original 217 o 'INFINITY', -> new InfinityLiteral $1.toString(), originalValue: $1.original 218 o 'NAN', -> new NaNLiteral $1 219 ] 220 221 # Assignment of a variable, property, or index to a value. 222 Assign: [ 223 o 'Assignable = Expression', -> new Assign $1, $3 224 o 'Assignable = TERMINATOR Expression', -> new Assign $1, $4 225 o 'Assignable = INDENT Expression OUTDENT', -> new Assign $1, $4 226 ] 227 228 # Assignment when it happens within an object literal. The difference from 229 # the ordinary **Assign** is that these allow numbers and strings as keys. 230 AssignObj: [ 231 o 'ObjAssignable', -> new Value $1 232 o 'ObjRestValue' 233 o 'ObjAssignable : Expression', -> new Assign LOC(1)(new Value $1), $3, 'object', 234 operatorToken: LOC(2)(new Literal $2) 235 o 'ObjAssignable : 236 INDENT Expression OUTDENT', -> new Assign LOC(1)(new Value $1), $4, 'object', 237 operatorToken: LOC(2)(new Literal $2) 238 o 'SimpleObjAssignable = Expression', -> new Assign LOC(1)(new Value $1), $3, null, 239 operatorToken: LOC(2)(new Literal $2) 240 o 'SimpleObjAssignable = 241 INDENT Expression OUTDENT', -> new Assign LOC(1)(new Value $1), $4, null, 242 operatorToken: LOC(2)(new Literal $2) 243 ] 244 245 SimpleObjAssignable: [ 246 o 'Identifier' 247 o 'Property' 248 o 'ThisProperty' 249 ] 250 251 ObjAssignable: [ 252 o 'SimpleObjAssignable' 253 o '[ Expression ]', -> new Value new ComputedPropertyName $2 254 o '@ [ Expression ]', -> new Value LOC(1)(new ThisLiteral $1), [LOC(3)(new ComputedPropertyName($3))], 'this' 255 o 'AlphaNumeric' 256 ] 257 258 # Object literal spread properties. 259 ObjRestValue: [ 260 o 'SimpleObjAssignable ...', -> new Splat new Value $1 261 o '... SimpleObjAssignable', -> new Splat new Value($2), postfix: no 262 o 'ObjSpreadExpr ...', -> new Splat $1 263 o '... ObjSpreadExpr', -> new Splat $2, postfix: no 264 ] 265 266 ObjSpreadExpr: [ 267 o 'ObjSpreadIdentifier' 268 o 'Object' 269 o 'Parenthetical' 270 o 'Super' 271 o 'This' 272 o 'SUPER OptFuncExist Arguments', -> new SuperCall LOC(1)(new Super), $3, $2.soak, $1 273 o 'DYNAMIC_IMPORT Arguments', -> new DynamicImportCall LOC(1)(new DynamicImport), $2 274 o 'SimpleObjAssignable OptFuncExist Arguments', -> new Call (new Value $1), $3, $2.soak 275 o 'ObjSpreadExpr OptFuncExist Arguments', -> new Call $1, $3, $2.soak 276 ] 277 278 ObjSpreadIdentifier: [ 279 o 'SimpleObjAssignable Accessor', -> (new Value $1).add $2 280 o 'ObjSpreadExpr Accessor', -> (new Value $1).add $2 281 ] 282 283 # A return statement from a function body. 284 Return: [ 285 o 'RETURN Expression', -> new Return $2 286 o 'RETURN INDENT Object OUTDENT', -> new Return new Value $3 287 o 'RETURN', -> new Return 288 ] 289 290 YieldReturn: [ 291 o 'YIELD RETURN Expression', -> new YieldReturn $3, returnKeyword: LOC(2)(new Literal $2) 292 o 'YIELD RETURN', -> new YieldReturn null, returnKeyword: LOC(2)(new Literal $2) 293 ] 294 295 AwaitReturn: [ 296 o 'AWAIT RETURN Expression', -> new AwaitReturn $3, returnKeyword: LOC(2)(new Literal $2) 297 o 'AWAIT RETURN', -> new AwaitReturn null, returnKeyword: LOC(2)(new Literal $2) 298 ] 299 300 # The **Code** node is the function literal. It's defined by an indented block 301 # of **Block** preceded by a function arrow, with an optional parameter list. 302 Code: [ 303 o 'PARAM_START ParamList PARAM_END FuncGlyph Block', -> new Code $2, $5, $4, LOC(1)(new Literal $1) 304 o 'FuncGlyph Block', -> new Code [], $2, $1 305 ] 306 307 # The Codeline is the **Code** node with **Line** instead of indented **Block**. 308 CodeLine: [ 309 o 'PARAM_START ParamList PARAM_END FuncGlyph Line', -> new Code $2, LOC(5)(Block.wrap [$5]), $4, 310 LOC(1)(new Literal $1) 311 o 'FuncGlyph Line', -> new Code [], LOC(2)(Block.wrap [$2]), $1 312 ] 313 314 # CoffeeScript has two different symbols for functions. `->` is for ordinary 315 # functions, and `=>` is for functions bound to the current value of *this*. 316 FuncGlyph: [ 317 o '->', -> new FuncGlyph $1 318 o '=>', -> new FuncGlyph $1 319 ] 320 321 # An optional, trailing comma. 322 OptComma: [ 323 o '' 324 o ',' 325 ] 326 327 # The list of parameters that a function accepts can be of any length. 328 ParamList: [ 329 o '', -> [] 330 o 'Param', -> [$1] 331 o 'ParamList , Param', -> $1.concat $3 332 o 'ParamList OptComma TERMINATOR Param', -> $1.concat $4 333 o 'ParamList OptComma INDENT ParamList OptComma OUTDENT', -> $1.concat $4 334 ] 335 336 # A single parameter in a function definition can be ordinary, or a splat 337 # that hoovers up the remaining arguments. 338 Param: [ 339 o 'ParamVar', -> new Param $1 340 o 'ParamVar ...', -> new Param $1, null, on 341 o '... ParamVar', -> new Param $2, null, postfix: no 342 o 'ParamVar = Expression', -> new Param $1, $3 343 o '...', -> new Expansion 344 ] 345 346 # Function Parameters 347 ParamVar: [ 348 o 'Identifier' 349 o 'ThisProperty' 350 o 'Array' 351 o 'Object' 352 ] 353 354 # A splat that occurs outside of a parameter list. 355 Splat: [ 356 o 'Expression ...', -> new Splat $1 357 o '... Expression', -> new Splat $2, {postfix: no} 358 ] 359 360 # Variables and properties that can be assigned to. 361 SimpleAssignable: [ 362 o 'Identifier', -> new Value $1 363 o 'Value Accessor', -> $1.add $2 364 o 'Code Accessor', -> new Value($1).add $2 365 o 'ThisProperty' 366 ] 367 368 # Everything that can be assigned to. 369 Assignable: [ 370 o 'SimpleAssignable' 371 o 'Array', -> new Value $1 372 o 'Object', -> new Value $1 373 ] 374 375 # The types of things that can be treated as values -- assigned to, invoked 376 # as functions, indexed into, named as a class, etc. 377 Value: [ 378 o 'Assignable' 379 o 'Literal', -> new Value $1 380 o 'Parenthetical', -> new Value $1 381 o 'Range', -> new Value $1 382 o 'Invocation', -> new Value $1 383 o 'DoIife', -> new Value $1 384 o 'This' 385 o 'Super', -> new Value $1 386 o 'MetaProperty', -> new Value $1 387 ] 388 389 # A `super`-based expression that can be used as a value. 390 Super: [ 391 o 'SUPER . Property', -> new Super LOC(3)(new Access $3), LOC(1)(new Literal $1) 392 o 'SUPER INDEX_START Expression INDEX_END', -> new Super LOC(3)(new Index $3), LOC(1)(new Literal $1) 393 o 'SUPER INDEX_START INDENT Expression OUTDENT INDEX_END', -> new Super LOC(4)(new Index $4), LOC(1)(new Literal $1) 394 ] 395 396 # A "meta-property" access e.g. `new.target` 397 MetaProperty: [ 398 o 'NEW_TARGET . Property', -> new MetaProperty LOC(1)(new IdentifierLiteral $1), LOC(3)(new Access $3) 399 ] 400 401 # The general group of accessors into an object, by property, by prototype 402 # or by array index or slice. 403 Accessor: [ 404 o '. Property', -> new Access $2 405 o '?. Property', -> new Access $2, soak: yes 406 o ':: Property', -> [LOC(1)(new Access new PropertyName('prototype'), shorthand: yes), LOC(2)(new Access $2)] 407 o '?:: Property', -> [LOC(1)(new Access new PropertyName('prototype'), shorthand: yes, soak: yes), LOC(2)(new Access $2)] 408 o '::', -> new Access new PropertyName('prototype'), shorthand: yes 409 o '?::', -> new Access new PropertyName('prototype'), shorthand: yes, soak: yes 410 o 'Index' 411 ] 412 413 # Indexing into an object or array using bracket notation. 414 Index: [ 415 o 'INDEX_START IndexValue INDEX_END', -> $2 416 o 'INDEX_START INDENT IndexValue OUTDENT INDEX_END', -> $3 417 o 'INDEX_SOAK Index', -> extend $2, soak: yes 418 ] 419 420 IndexValue: [ 421 o 'Expression', -> new Index $1 422 o 'Slice', -> new Slice $1 423 ] 424 425 # In CoffeeScript, an object literal is simply a list of assignments. 426 Object: [ 427 o '{ AssignList OptComma }', -> new Obj $2, $1.generated 428 ] 429 430 # Assignment of properties within an object literal can be separated by 431 # comma, as in JavaScript, or simply by newline. 432 AssignList: [ 433 o '', -> [] 434 o 'AssignObj', -> [$1] 435 o 'AssignList , AssignObj', -> $1.concat $3 436 o 'AssignList OptComma TERMINATOR AssignObj', -> $1.concat $4 437 o 'AssignList OptComma INDENT AssignList OptComma OUTDENT', -> $1.concat $4 438 ] 439 440 # Class definitions have optional bodies of prototype property assignments, 441 # and optional references to the superclass. 442 Class: [ 443 o 'CLASS', -> new Class 444 o 'CLASS Block', -> new Class null, null, $2 445 o 'CLASS EXTENDS Expression', -> new Class null, $3 446 o 'CLASS EXTENDS Expression Block', -> new Class null, $3, $4 447 o 'CLASS SimpleAssignable', -> new Class $2 448 o 'CLASS SimpleAssignable Block', -> new Class $2, null, $3 449 o 'CLASS SimpleAssignable EXTENDS Expression', -> new Class $2, $4 450 o 'CLASS SimpleAssignable EXTENDS Expression Block', -> new Class $2, $4, $5 451 ] 452 453 Import: [ 454 o 'IMPORT String', -> new ImportDeclaration null, $2 455 o 'IMPORT ImportDefaultSpecifier FROM String', -> new ImportDeclaration new ImportClause($2, null), $4 456 o 'IMPORT ImportNamespaceSpecifier FROM String', -> new ImportDeclaration new ImportClause(null, $2), $4 457 o 'IMPORT { } FROM String', -> new ImportDeclaration new ImportClause(null, new ImportSpecifierList []), $5 458 o 'IMPORT { ImportSpecifierList OptComma } FROM String', -> new ImportDeclaration new ImportClause(null, new ImportSpecifierList $3), $7 459 o 'IMPORT ImportDefaultSpecifier , ImportNamespaceSpecifier FROM String', -> new ImportDeclaration new ImportClause($2, $4), $6 460 o 'IMPORT ImportDefaultSpecifier , { ImportSpecifierList OptComma } FROM String', -> new ImportDeclaration new ImportClause($2, new ImportSpecifierList $5), $9 461 ] 462 463 ImportSpecifierList: [ 464 o 'ImportSpecifier', -> [$1] 465 o 'ImportSpecifierList , ImportSpecifier', -> $1.concat $3 466 o 'ImportSpecifierList OptComma TERMINATOR ImportSpecifier', -> $1.concat $4 467 o 'INDENT ImportSpecifierList OptComma OUTDENT', -> $2 468 o 'ImportSpecifierList OptComma INDENT ImportSpecifierList OptComma OUTDENT', -> $1.concat $4 469 ] 470 471 ImportSpecifier: [ 472 o 'Identifier', -> new ImportSpecifier $1 473 o 'Identifier AS Identifier', -> new ImportSpecifier $1, $3 474 o 'DEFAULT', -> new ImportSpecifier LOC(1)(new DefaultLiteral $1) 475 o 'DEFAULT AS Identifier', -> new ImportSpecifier LOC(1)(new DefaultLiteral($1)), $3 476 ] 477 478 ImportDefaultSpecifier: [ 479 o 'Identifier', -> new ImportDefaultSpecifier $1 480 ] 481 482 ImportNamespaceSpecifier: [ 483 o 'IMPORT_ALL AS Identifier', -> new ImportNamespaceSpecifier new Literal($1), $3 484 ] 485 486 Export: [ 487 o 'EXPORT { }', -> new ExportNamedDeclaration new ExportSpecifierList [] 488 o 'EXPORT { ExportSpecifierList OptComma }', -> new ExportNamedDeclaration new ExportSpecifierList $3 489 o 'EXPORT Class', -> new ExportNamedDeclaration $2 490 o 'EXPORT Identifier = Expression', -> new ExportNamedDeclaration LOC(2,4)(new Assign $2, $4, null, 491 moduleDeclaration: 'export') 492 o 'EXPORT Identifier = TERMINATOR Expression', -> new ExportNamedDeclaration LOC(2,5)(new Assign $2, $5, null, 493 moduleDeclaration: 'export') 494 o 'EXPORT Identifier = INDENT Expression OUTDENT', -> new ExportNamedDeclaration LOC(2,6)(new Assign $2, $5, null, 495 moduleDeclaration: 'export') 496 o 'EXPORT DEFAULT Expression', -> new ExportDefaultDeclaration $3 497 o 'EXPORT DEFAULT INDENT Object OUTDENT', -> new ExportDefaultDeclaration new Value $4 498 o 'EXPORT EXPORT_ALL FROM String', -> new ExportAllDeclaration new Literal($2), $4 499 o 'EXPORT { } FROM String', -> new ExportNamedDeclaration new ExportSpecifierList([]), $5 500 o 'EXPORT { ExportSpecifierList OptComma } FROM String', -> new ExportNamedDeclaration new ExportSpecifierList($3), $7 501 ] 502 503 ExportSpecifierList: [ 504 o 'ExportSpecifier', -> [$1] 505 o 'ExportSpecifierList , ExportSpecifier', -> $1.concat $3 506 o 'ExportSpecifierList OptComma TERMINATOR ExportSpecifier', -> $1.concat $4 507 o 'INDENT ExportSpecifierList OptComma OUTDENT', -> $2 508 o 'ExportSpecifierList OptComma INDENT ExportSpecifierList OptComma OUTDENT', -> $1.concat $4 509 ] 510 511 ExportSpecifier: [ 512 o 'Identifier', -> new ExportSpecifier $1 513 o 'Identifier AS Identifier', -> new ExportSpecifier $1, $3 514 o 'Identifier AS DEFAULT', -> new ExportSpecifier $1, LOC(3)(new DefaultLiteral $3) 515 o 'DEFAULT', -> new ExportSpecifier LOC(1)(new DefaultLiteral $1) 516 o 'DEFAULT AS Identifier', -> new ExportSpecifier LOC(1)(new DefaultLiteral($1)), $3 517 ] 518 519 # Ordinary function invocation, or a chained series of calls. 520 Invocation: [ 521 o 'Value OptFuncExist String', -> new TaggedTemplateCall $1, $3, $2.soak 522 o 'Value OptFuncExist Arguments', -> new Call $1, $3, $2.soak 523 o 'SUPER OptFuncExist Arguments', -> new SuperCall LOC(1)(new Super), $3, $2.soak, $1 524 o 'DYNAMIC_IMPORT Arguments', -> new DynamicImportCall LOC(1)(new DynamicImport), $2 525 ] 526 527 # An optional existence check on a function. 528 OptFuncExist: [ 529 o '', -> soak: no 530 o 'FUNC_EXIST', -> soak: yes 531 ] 532 533 # The list of arguments to a function call. 534 Arguments: [ 535 o 'CALL_START CALL_END', -> [] 536 o 'CALL_START ArgList OptComma CALL_END', -> $2.implicit = $1.generated; $2 537 ] 538 539 # A reference to the *this* current object. 540 This: [ 541 o 'THIS', -> new Value new ThisLiteral $1 542 o '@', -> new Value new ThisLiteral $1 543 ] 544 545 # A reference to a property on *this*. 546 ThisProperty: [ 547 o '@ Property', -> new Value LOC(1)(new ThisLiteral $1), [LOC(2)(new Access($2))], 'this' 548 ] 549 550 # The array literal. 551 Array: [ 552 o '[ ]', -> new Arr [] 553 o '[ Elisions ]', -> new Arr $2 554 o '[ ArgElisionList OptElisions ]', -> new Arr [].concat $2, $3 555 ] 556 557 # Inclusive and exclusive range dots. 558 RangeDots: [ 559 o '..', -> exclusive: no 560 o '...', -> exclusive: yes 561 ] 562 563 # The CoffeeScript range literal. 564 Range: [ 565 o '[ Expression RangeDots Expression ]', -> new Range $2, $4, if $3.exclusive then 'exclusive' else 'inclusive' 566 o '[ ExpressionLine RangeDots Expression ]', -> new Range $2, $4, if $3.exclusive then 'exclusive' else 'inclusive' 567 ] 568 569 # Array slice literals. 570 Slice: [ 571 o 'Expression RangeDots Expression', -> new Range $1, $3, if $2.exclusive then 'exclusive' else 'inclusive' 572 o 'Expression RangeDots', -> new Range $1, null, if $2.exclusive then 'exclusive' else 'inclusive' 573 o 'ExpressionLine RangeDots Expression', -> new Range $1, $3, if $2.exclusive then 'exclusive' else 'inclusive' 574 o 'ExpressionLine RangeDots', -> new Range $1, null, if $2.exclusive then 'exclusive' else 'inclusive' 575 o 'RangeDots Expression', -> new Range null, $2, if $1.exclusive then 'exclusive' else 'inclusive' 576 o 'RangeDots', -> new Range null, null, if $1.exclusive then 'exclusive' else 'inclusive' 577 ] 578 579 # The **ArgList** is the list of objects passed into a function call 580 # (i.e. comma-separated expressions). Newlines work as well. 581 ArgList: [ 582 o 'Arg', -> [$1] 583 o 'ArgList , Arg', -> $1.concat $3 584 o 'ArgList OptComma TERMINATOR Arg', -> $1.concat $4 585 o 'INDENT ArgList OptComma OUTDENT', -> $2 586 o 'ArgList OptComma INDENT ArgList OptComma OUTDENT', -> $1.concat $4 587 ] 588 589 # Valid arguments are Blocks or Splats. 590 Arg: [ 591 o 'Expression' 592 o 'ExpressionLine' 593 o 'Splat' 594 o '...', -> new Expansion 595 ] 596 597 # The **ArgElisionList** is the list of objects, contents of an array literal 598 # (i.e. comma-separated expressions and elisions). Newlines work as well. 599 ArgElisionList: [ 600 o 'ArgElision' 601 o 'ArgElisionList , ArgElision', -> $1.concat $3 602 o 'ArgElisionList OptComma TERMINATOR ArgElision', -> $1.concat $4 603 o 'INDENT ArgElisionList OptElisions OUTDENT', -> $2.concat $3 604 o 'ArgElisionList OptElisions INDENT ArgElisionList OptElisions OUTDENT', -> $1.concat $2, $4, $5 605 ] 606 607 ArgElision: [ 608 o 'Arg', -> [$1] 609 o 'Elisions Arg', -> $1.concat $2 610 ] 611 612 OptElisions: [ 613 o 'OptComma', -> [] 614 o ', Elisions', -> [].concat $2 615 ] 616 617 Elisions: [ 618 o 'Elision', -> [$1] 619 o 'Elisions Elision', -> $1.concat $2 620 ] 621 622 Elision: [ 623 o ',', -> new Elision 624 o 'Elision TERMINATOR', -> $1 625 ] 626 627 # Just simple, comma-separated, required arguments (no fancy syntax). We need 628 # this to be separate from the **ArgList** for use in **Switch** blocks, where 629 # having the newlines wouldn't make sense. 630 SimpleArgs: [ 631 o 'Expression' 632 o 'ExpressionLine' 633 o 'SimpleArgs , Expression', -> [].concat $1, $3 634 o 'SimpleArgs , ExpressionLine', -> [].concat $1, $3 635 ] 636 637 # The variants of *try/catch/finally* exception handling blocks. 638 Try: [ 639 o 'TRY Block', -> new Try $2 640 o 'TRY Block Catch', -> new Try $2, $3 641 o 'TRY Block FINALLY Block', -> new Try $2, null, $4, LOC(3)(new Literal $3) 642 o 'TRY Block Catch FINALLY Block', -> new Try $2, $3, $5, LOC(4)(new Literal $4) 643 ] 644 645 # A catch clause names its error and runs a block of code. 646 Catch: [ 647 o 'CATCH Identifier Block', -> new Catch $3, $2 648 o 'CATCH Object Block', -> new Catch $3, LOC(2)(new Value($2)) 649 o 'CATCH Block', -> new Catch $2 650 ] 651 652 # Throw an exception object. 653 Throw: [ 654 o 'THROW Expression', -> new Throw $2 655 o 'THROW INDENT Object OUTDENT', -> new Throw new Value $3 656 ] 657 658 # Parenthetical expressions. Note that the **Parenthetical** is a **Value**, 659 # not an **Expression**, so if you need to use an expression in a place 660 # where only values are accepted, wrapping it in parentheses will always do 661 # the trick. 662 Parenthetical: [ 663 o '( Body )', -> new Parens $2 664 o '( INDENT Body OUTDENT )', -> new Parens $3 665 ] 666 667 # The condition portion of a while loop. 668 WhileLineSource: [ 669 o 'WHILE ExpressionLine', -> new While $2 670 o 'WHILE ExpressionLine WHEN ExpressionLine', -> new While $2, guard: $4 671 o 'UNTIL ExpressionLine', -> new While $2, invert: true 672 o 'UNTIL ExpressionLine WHEN ExpressionLine', -> new While $2, invert: true, guard: $4 673 ] 674 675 WhileSource: [ 676 o 'WHILE Expression', -> new While $2 677 o 'WHILE Expression WHEN Expression', -> new While $2, guard: $4 678 o 'WHILE ExpressionLine WHEN Expression', -> new While $2, guard: $4 679 o 'UNTIL Expression', -> new While $2, invert: true 680 o 'UNTIL Expression WHEN Expression', -> new While $2, invert: true, guard: $4 681 o 'UNTIL ExpressionLine WHEN Expression', -> new While $2, invert: true, guard: $4 682 ] 683 684 # The while loop can either be normal, with a block of expressions to execute, 685 # or postfix, with a single expression. There is no do..while. 686 While: [ 687 o 'WhileSource Block', -> $1.addBody $2 688 o 'WhileLineSource Block', -> $1.addBody $2 689 o 'Statement WhileSource', -> (Object.assign $2, postfix: yes).addBody LOC(1) Block.wrap([$1]) 690 o 'Expression WhileSource', -> (Object.assign $2, postfix: yes).addBody LOC(1) Block.wrap([$1]) 691 o 'Loop', -> $1 692 ] 693 694 Loop: [ 695 o 'LOOP Block', -> new While(LOC(1)(new BooleanLiteral 'true'), isLoop: yes).addBody $2 696 o 'LOOP Expression', -> new While(LOC(1)(new BooleanLiteral 'true'), isLoop: yes).addBody LOC(2) Block.wrap [$2] 697 ] 698 699 # Array, object, and range comprehensions, at the most generic level. 700 # Comprehensions can either be normal, with a block of expressions to execute, 701 # or postfix, with a single expression. 702 For: [ 703 o 'Statement ForBody', -> $2.postfix = yes; $2.addBody $1 704 o 'Expression ForBody', -> $2.postfix = yes; $2.addBody $1 705 o 'ForBody Block', -> $1.addBody $2 706 o 'ForLineBody Block', -> $1.addBody $2 707 ] 708 709 ForBody: [ 710 o 'FOR Range', -> new For [], source: (LOC(2) new Value($2)) 711 o 'FOR Range BY Expression', -> new For [], source: (LOC(2) new Value($2)), step: $4 712 o 'ForStart ForSource', -> $1.addSource $2 713 ] 714 715 ForLineBody: [ 716 o 'FOR Range BY ExpressionLine', -> new For [], source: (LOC(2) new Value($2)), step: $4 717 o 'ForStart ForLineSource', -> $1.addSource $2 718 ] 719 720 ForStart: [ 721 o 'FOR ForVariables', -> new For [], name: $2[0], index: $2[1] 722 o 'FOR AWAIT ForVariables', -> 723 [name, index] = $3 724 new For [], {name, index, await: yes, awaitTag: (LOC(2) new Literal($2))} 725 o 'FOR OWN ForVariables', -> 726 [name, index] = $3 727 new For [], {name, index, own: yes, ownTag: (LOC(2) new Literal($2))} 728 ] 729 730 # An array of all accepted values for a variable inside the loop. 731 # This enables support for pattern matching. 732 ForValue: [ 733 o 'Identifier' 734 o 'ThisProperty' 735 o 'Array', -> new Value $1 736 o 'Object', -> new Value $1 737 ] 738 739 # An array or range comprehension has variables for the current element 740 # and (optional) reference to the current index. Or, *key, value*, in the case 741 # of object comprehensions. 742 ForVariables: [ 743 o 'ForValue', -> [$1] 744 o 'ForValue , ForValue', -> [$1, $3] 745 ] 746 747 # The source of a comprehension is an array or object with an optional guard 748 # clause. If it's an array comprehension, you can also choose to step through 749 # in fixed-size increments. 750 ForSource: [ 751 o 'FORIN Expression', -> source: $2 752 o 'FOROF Expression', -> source: $2, object: yes 753 o 'FORIN Expression WHEN Expression', -> source: $2, guard: $4 754 o 'FORIN ExpressionLine WHEN Expression', -> source: $2, guard: $4 755 o 'FOROF Expression WHEN Expression', -> source: $2, guard: $4, object: yes 756 o 'FOROF ExpressionLine WHEN Expression', -> source: $2, guard: $4, object: yes 757 o 'FORIN Expression BY Expression', -> source: $2, step: $4 758 o 'FORIN ExpressionLine BY Expression', -> source: $2, step: $4 759 o 'FORIN Expression WHEN Expression BY Expression', -> source: $2, guard: $4, step: $6 760 o 'FORIN ExpressionLine WHEN Expression BY Expression', -> source: $2, guard: $4, step: $6 761 o 'FORIN Expression WHEN ExpressionLine BY Expression', -> source: $2, guard: $4, step: $6 762 o 'FORIN ExpressionLine WHEN ExpressionLine BY Expression', -> source: $2, guard: $4, step: $6 763 o 'FORIN Expression BY Expression WHEN Expression', -> source: $2, step: $4, guard: $6 764 o 'FORIN ExpressionLine BY Expression WHEN Expression', -> source: $2, step: $4, guard: $6 765 o 'FORIN Expression BY ExpressionLine WHEN Expression', -> source: $2, step: $4, guard: $6 766 o 'FORIN ExpressionLine BY ExpressionLine WHEN Expression', -> source: $2, step: $4, guard: $6 767 o 'FORFROM Expression', -> source: $2, from: yes 768 o 'FORFROM Expression WHEN Expression', -> source: $2, guard: $4, from: yes 769 o 'FORFROM ExpressionLine WHEN Expression', -> source: $2, guard: $4, from: yes 770 ] 771 772 ForLineSource: [ 773 o 'FORIN ExpressionLine', -> source: $2 774 o 'FOROF ExpressionLine', -> source: $2, object: yes 775 o 'FORIN Expression WHEN ExpressionLine', -> source: $2, guard: $4 776 o 'FORIN ExpressionLine WHEN ExpressionLine', -> source: $2, guard: $4 777 o 'FOROF Expression WHEN ExpressionLine', -> source: $2, guard: $4, object: yes 778 o 'FOROF ExpressionLine WHEN ExpressionLine', -> source: $2, guard: $4, object: yes 779 o 'FORIN Expression BY ExpressionLine', -> source: $2, step: $4 780 o 'FORIN ExpressionLine BY ExpressionLine', -> source: $2, step: $4 781 o 'FORIN Expression WHEN Expression BY ExpressionLine', -> source: $2, guard: $4, step: $6 782 o 'FORIN ExpressionLine WHEN Expression BY ExpressionLine', -> source: $2, guard: $4, step: $6 783 o 'FORIN Expression WHEN ExpressionLine BY ExpressionLine', -> source: $2, guard: $4, step: $6 784 o 'FORIN ExpressionLine WHEN ExpressionLine BY ExpressionLine', -> source: $2, guard: $4, step: $6 785 o 'FORIN Expression BY Expression WHEN ExpressionLine', -> source: $2, step: $4, guard: $6 786 o 'FORIN ExpressionLine BY Expression WHEN ExpressionLine', -> source: $2, step: $4, guard: $6 787 o 'FORIN Expression BY ExpressionLine WHEN ExpressionLine', -> source: $2, step: $4, guard: $6 788 o 'FORIN ExpressionLine BY ExpressionLine WHEN ExpressionLine', -> source: $2, step: $4, guard: $6 789 o 'FORFROM ExpressionLine', -> source: $2, from: yes 790 o 'FORFROM Expression WHEN ExpressionLine', -> source: $2, guard: $4, from: yes 791 o 'FORFROM ExpressionLine WHEN ExpressionLine', -> source: $2, guard: $4, from: yes 792 ] 793 794 Switch: [ 795 o 'SWITCH Expression INDENT Whens OUTDENT', -> new Switch $2, $4 796 o 'SWITCH ExpressionLine INDENT Whens OUTDENT', -> new Switch $2, $4 797 o 'SWITCH Expression INDENT Whens ELSE Block OUTDENT', -> new Switch $2, $4, LOC(5,6) $6 798 o 'SWITCH ExpressionLine INDENT Whens ELSE Block OUTDENT', -> new Switch $2, $4, LOC(5,6) $6 799 o 'SWITCH INDENT Whens OUTDENT', -> new Switch null, $3 800 o 'SWITCH INDENT Whens ELSE Block OUTDENT', -> new Switch null, $3, LOC(4,5) $5 801 ] 802 803 Whens: [ 804 o 'When', -> [$1] 805 o 'Whens When', -> $1.concat $2 806 ] 807 808 # An individual **When** clause, with action. 809 When: [ 810 o 'LEADING_WHEN SimpleArgs Block', -> new SwitchWhen $2, $3 811 o 'LEADING_WHEN SimpleArgs Block TERMINATOR', -> LOC(1, 3) new SwitchWhen $2, $3 812 ] 813 814 # The most basic form of *if* is a condition and an action. The following 815 # if-related rules are broken up along these lines in order to avoid 816 # ambiguity. 817 IfBlock: [ 818 o 'IF Expression Block', -> new If $2, $3, type: $1 819 o 'IfBlock ELSE IF Expression Block', -> $1.addElse LOC(3,5) new If $4, $5, type: $3 820 ] 821 822 # The full complement of *if* expressions, including postfix one-liner 823 # *if* and *unless*. 824 If: [ 825 o 'IfBlock' 826 o 'IfBlock ELSE Block', -> $1.addElse $3 827 o 'Statement POST_IF Expression', -> new If $3, LOC(1)(Block.wrap [$1]), type: $2, postfix: true 828 o 'Expression POST_IF Expression', -> new If $3, LOC(1)(Block.wrap [$1]), type: $2, postfix: true 829 ] 830 831 IfBlockLine: [ 832 o 'IF ExpressionLine Block', -> new If $2, $3, type: $1 833 o 'IfBlockLine ELSE IF ExpressionLine Block', -> $1.addElse LOC(3,5) new If $4, $5, type: $3 834 ] 835 836 IfLine: [ 837 o 'IfBlockLine' 838 o 'IfBlockLine ELSE Block', -> $1.addElse $3 839 o 'Statement POST_IF ExpressionLine', -> new If $3, LOC(1)(Block.wrap [$1]), type: $2, postfix: true 840 o 'Expression POST_IF ExpressionLine', -> new If $3, LOC(1)(Block.wrap [$1]), type: $2, postfix: true 841 ] 842 843 # Arithmetic and logical operators, working on one or more operands. 844 # Here they are grouped by order of precedence. The actual precedence rules 845 # are defined at the bottom of the page. It would be shorter if we could 846 # combine most of these rules into a single generic *Operand OpSymbol Operand* 847 # -type rule, but in order to make the precedence binding possible, separate 848 # rules are necessary. 849 OperationLine: [ 850 o 'UNARY ExpressionLine', -> new Op $1, $2 851 o 'DO ExpressionLine', -> new Op $1, $2 852 o 'DO_IIFE CodeLine', -> new Op $1, $2 853 ] 854 855 Operation: [ 856 o 'UNARY Expression', -> new Op $1.toString(), $2, undefined, undefined, originalOperator: $1.original 857 o 'DO Expression', -> new Op $1, $2 858 o 'UNARY_MATH Expression', -> new Op $1, $2 859 o '- Expression', (-> new Op '-', $2), prec: 'UNARY_MATH' 860 o '+ Expression', (-> new Op '+', $2), prec: 'UNARY_MATH' 861 862 o 'AWAIT Expression', -> new Op $1, $2 863 o 'AWAIT INDENT Object OUTDENT', -> new Op $1, $3 864 865 o '-- SimpleAssignable', -> new Op '--', $2 866 o '++ SimpleAssignable', -> new Op '++', $2 867 o 'SimpleAssignable --', -> new Op '--', $1, null, true 868 o 'SimpleAssignable ++', -> new Op '++', $1, null, true 869 870 # [The existential operator](https://coffeescript.org/#existential-operator). 871 o 'Expression ?', -> new Existence $1 872 873 o 'Expression + Expression', -> new Op '+' , $1, $3 874 o 'Expression - Expression', -> new Op '-' , $1, $3 875 876 o 'Expression MATH Expression', -> new Op $2, $1, $3 877 o 'Expression ** Expression', -> new Op $2, $1, $3 878 o 'Expression SHIFT Expression', -> new Op $2, $1, $3 879 o 'Expression COMPARE Expression', -> new Op $2.toString(), $1, $3, undefined, originalOperator: $2.original 880 o 'Expression & Expression', -> new Op $2, $1, $3 881 o 'Expression ^ Expression', -> new Op $2, $1, $3 882 o 'Expression | Expression', -> new Op $2, $1, $3 883 o 'Expression && Expression', -> new Op $2.toString(), $1, $3, undefined, originalOperator: $2.original 884 o 'Expression || Expression', -> new Op $2.toString(), $1, $3, undefined, originalOperator: $2.original 885 o 'Expression BIN? Expression', -> new Op $2, $1, $3 886 o 'Expression RELATION Expression', -> new Op $2.toString(), $1, $3, undefined, invertOperator: $2.invert?.original ? $2.invert 887 888 o 'SimpleAssignable COMPOUND_ASSIGN 889 Expression', -> new Assign $1, $3, $2.toString(), originalContext: $2.original 890 o 'SimpleAssignable COMPOUND_ASSIGN 891 INDENT Expression OUTDENT', -> new Assign $1, $4, $2.toString(), originalContext: $2.original 892 o 'SimpleAssignable COMPOUND_ASSIGN TERMINATOR 893 Expression', -> new Assign $1, $4, $2.toString(), originalContext: $2.original 894 ] 895 896 DoIife: [ 897 o 'DO_IIFE Code', -> new Op $1 , $2 898 ] 899 900# Precedence 901# ---------- 902 903# Operators at the top of this list have higher precedence than the ones lower 904# down. Following these rules is what makes `2 + 3 * 4` parse as: 905# 906# 2 + (3 * 4) 907# 908# And not: 909# 910# (2 + 3) * 4 911operators = [ 912 ['right', 'DO_IIFE'] 913 ['left', '.', '?.', '::', '?::'] 914 ['left', 'CALL_START', 'CALL_END'] 915 ['nonassoc', '++', '--'] 916 ['left', '?'] 917 ['right', 'UNARY', 'DO'] 918 ['right', 'AWAIT'] 919 ['right', '**'] 920 ['right', 'UNARY_MATH'] 921 ['left', 'MATH'] 922 ['left', '+', '-'] 923 ['left', 'SHIFT'] 924 ['left', 'RELATION'] 925 ['left', 'COMPARE'] 926 ['left', '&'] 927 ['left', '^'] 928 ['left', '|'] 929 ['left', '&&'] 930 ['left', '||'] 931 ['left', 'BIN?'] 932 ['nonassoc', 'INDENT', 'OUTDENT'] 933 ['right', 'YIELD'] 934 ['right', '=', ':', 'COMPOUND_ASSIGN', 'RETURN', 'THROW', 'EXTENDS'] 935 ['right', 'FORIN', 'FOROF', 'FORFROM', 'BY', 'WHEN'] 936 ['right', 'IF', 'ELSE', 'FOR', 'WHILE', 'UNTIL', 'LOOP', 'SUPER', 'CLASS', 'IMPORT', 'EXPORT', 'DYNAMIC_IMPORT'] 937 ['left', 'POST_IF'] 938] 939 940# Wrapping Up 941# ----------- 942 943# Finally, now that we have our **grammar** and our **operators**, we can create 944# our **Jison.Parser**. We do this by processing all of our rules, recording all 945# terminals (every symbol which does not appear as the name of a rule above) 946# as "tokens". 947tokens = [] 948for name, alternatives of grammar 949 grammar[name] = for alt in alternatives 950 for token in alt[0].split ' ' 951 tokens.push token unless grammar[token] 952 alt[1] = "return #{alt[1]}" if name is 'Root' 953 alt 954 955# Initialize the **Parser** with our list of terminal **tokens**, our **grammar** 956# rules, and the name of the root. Reverse the operators because Jison orders 957# precedence from low to high, and we have it high to low 958# (as in [Yacc](http://dinosaur.compilertools.net/yacc/index.html)). 959exports.parser = new Parser 960 tokens : tokens.join ' ' 961 bnf : grammar 962 operators : operators.reverse() 963 startSymbol : 'Root'