Reads FunctionalScript source as tokens, one per line. Each line shows the starting line and column, the token kind, and its value or diagnostic; whitespace and comments are omitted.

Example OverviewA failure at run timeParse errorCommentsWhitespaceNon-breaking spaceIdentifiersNon-ASCII identifierString escapesHex escapePrimitivesTemplate literalsObjectsA repeated object keyShorthand membersNamed exportsAn importA named import and a callSharing: a const used twiceSharing: a repeated expressionVariablesVariables: a snapshot for a closureDestructuringDestructuring: an elisionOperator precedenceArithmeticLogical nottypeofLaziness: && || ??Laziness: ?:Comma: the assertion formComma: a detached callinstanceofinNumber conversionMethods and propertiesOptional chainingOptional chaining: a long chainThe entry helperLazinessFunction with a rest parameterClosureRecursionRecursion: AckermannCall statementsEarly returnThrowLoopLoop over a parameterLoop with two variablesLoop with a conditionalLoop with alternative branchesNested loopsLoop with break and continueLoop with return and throwLoop with switchLoop with no stateSequential loopsLoop in a guardModule loopLoop between exportsSwitchStatic functionsObject.entries

Source const a = 1 + 2; const checked = a.x; export default [a, a, a * 3, a < 4 && a, (...x) => x, undefined];​const a = 1 + 2; const checked = a.x; export default [a, a, a * 3, a < 4 && a, (...x) => x, undefined];

Tokens, line:column, kind and value:

1:1  id  "const"
1:7  id  "a"
1:9  =
1:11  number  "1"
1:13  +
1:15  number  "2"
1:16  ;
2:1  id  "const"
2:7  id  "checked"
2:15  =
2:17  id  "a"
2:18  .
2:19  id  "x"
2:20  ;
3:1  id  "export"
3:8  id  "default"
3:16  [
3:17  id  "a"
3:18  ,
3:20  id  "a"
3:21  ,
3:23  id  "a"
3:25  *
3:27  number  "3"
3:28  ,
3:30  id  "a"
3:32  <
3:34  number  "4"
3:36  &&
3:39  id  "a"
3:40  ,
3:42  (
3:43  ...
3:46  id  "x"
3:47  )
3:49  =>
3:52  id  "x"
3:53  ,
3:55  undefined
3:64  ]
3:65  ;
3:66  eof