Pure ESM

examples/grammars/.gitignore

@@ -0,0 +1 @@
+./graphql/gen/graphql-bundled.min.mjs

examples/grammars/calculator/calculator_embedded_actions.js

@@ -1,4 +1,3 @@
-"use strict"
 /**
  * An Example of implementing a Calculator with embedded actions (semantics).
  *
@@ -10,12 +9,12 @@
  * for an alternative:
  * https://github.com/chevrotain/chevrotain/blob/master/examples/grammars/calculator/calculator_pure_grammar.js
  */
-const {
+import {
  createToken,
  Lexer,
  EmbeddedActionsParser,
  tokenMatcher
-} = require("chevrotain")
+} from "chevrotain"
 
 // ----------------- lexer -----------------
 // using the NA pattern marks this Token class as 'irrelevant' for the Lexer.
@@ -194,7 +193,7 @@ class Calculator extends EmbeddedActionsParser {
 const parser = new Calculator()
 
 // wrapping it all together
-module.exports = function (text) {
+export function parseEmbedded(text) {
  const lexResult = CalculatorLexer.tokenize(text)
  // setting a new input will RESET the parser instance's state.
  parser.input = lexResult.tokens

examples/grammars/calculator/calculator_pure_grammar.js

@@ -1,4 +1,3 @@
-"use strict"
 /**
  * An Example of implementing a Calculator with separated grammar and semantics (actions).
  * This separation makes it easier to maintain the grammar and reuse it in different use cases.
@@ -9,7 +8,7 @@
  * See farther details here:
  * https://chevrotain.io/docs/guide/concrete_syntax_tree.html
  */
-const { createToken, tokenMatcher, Lexer, CstParser } = require("chevrotain")
+import { createToken, tokenMatcher, Lexer, CstParser } from "chevrotain"
 
 // ----------------- lexer -----------------
 // using the NA pattern marks this Token class as 'irrelevant' for the Lexer.
@@ -242,7 +241,7 @@ class CalculatorInterpreter extends BaseCstVisitor {
 // We only need a single interpreter instance because our interpreter has no state.
 const interpreter = new CalculatorInterpreter()
 
-module.exports = function (text) {
+export function parsePure(text) {
  // 1. Tokenize the input.
  const lexResult = CalculatorLexer.tokenize(text)
 

examples/grammars/calculator/calculator_spec.js

@@ -1,51 +1,51 @@
-const assert = require("assert")
+import assert from "assert"
+import { parseEmbedded } from "./calculator_embedded_actions.js"
+import { parsePure } from "./calculator_pure_grammar.js"
 
 describe("The Calculator Grammar", () => {
  context("Embedded Actions", () => {
- const calc = require("./calculator_embedded_actions")
  it("can calculate an expression", () => {
- assert.equal(calc("1 + 2").value, 3)
+ assert.equal(parseEmbedded("1 + 2").value, 3)
  })
 
  it("can calculate an expression with operator precedence", () => {
  // if it was evaluated left to right without taking into account precedence the result would have been 9
- assert.equal(calc("1 + 2 * 3").value, 7)
+ assert.equal(parseEmbedded("1 + 2 * 3").value, 7)
  })
 
  it("can calculate an expression with operator precedence #2", () => {
- assert.equal(calc("(1 + 2) * 3").value, 9)
+ assert.equal(parseEmbedded("(1 + 2) * 3").value, 9)
  })
 
  it("can calculate an expression with many parenthesis", () => {
- assert.equal(calc("((((666))))").value, 666)
+ assert.equal(parseEmbedded("((((666))))").value, 666)
  })
 
  it("can calculate an expression with power function", () => {
- assert.equal(calc("1 + power(2,2)").value, 5)
+ assert.equal(parseEmbedded("1 + power(2,2)").value, 5)
  })
  })
 
  context("Pure Grammar with Separated Semantics", () => {
- const calc = require("./calculator_pure_grammar")
  it("can calculate an expression", () => {
- assert.equal(calc("1 + 2").value, 3)
+ assert.equal(parsePure("1 + 2").value, 3)
  })
 
  it("can calculate an expression with operator precedence", () => {
  // if it was evaluated left to right without taking into account precedence the result would have been 9
- assert.equal(calc("1 + 2 * 3").value, 7)
+ assert.equal(parsePure("1 + 2 * 3").value, 7)
  })
 
  it("can calculate an expression with operator precedence #2", () => {
- assert.equal(calc("(1 + 2) * 3").value, 9)
+ assert.equal(parsePure("(1 + 2) * 3").value, 9)
  })
 
  it("can calculate an expression with many parenthesis", () => {
- assert.equal(calc("((((666))))").value, 666)
+ assert.equal(parsePure("((((666))))").value, 666)
  })
 
  it("can calculate an expression with power function", () => {
- assert.equal(calc("1 + power(2,2)").value, 5)
+ assert.equal(parsePure("1 + power(2,2)").value, 5)
  })
  })
 })

examples/grammars/css/css.js

@@ -1,6 +1,5 @@
-const XRegExp = require("xregexp")
-const chevrotain = require("chevrotain")
-const { Lexer, CstParser } = chevrotain
+import XRegExp from "xregexp"
+import { Lexer, CstParser, createToken as orgCreateToken } from "chevrotain"
 
 // ----------------- lexer -----------------
 // Based on the specs in:
@@ -23,7 +22,7 @@ function MAKE_PATTERN(def, flags) {
 // array of cssTokens
 const cssTokens = []
 const createToken = function () {
- const newToken = chevrotain.createToken.apply(null, arguments)
+ const newToken = orgCreateToken.apply(null, arguments)
  cssTokens.push(newToken)
  return newToken
 }
@@ -607,18 +606,16 @@ class CssParser extends CstParser {
 // reuse the same parser instance.
 const parser = new CssParser()
 
-module.exports = {
- parseCss: function (text) {
- const lexResult = CssLexer.tokenize(text)
- // setting a new input will RESET the parser instance's state.
- parser.input = lexResult.tokens
- // any top level rule may be used as an entry point
- const cst = parser.stylesheet()
-
- return {
- cst: cst,
- lexErrors: lexResult.errors,
- parseErrors: parser.errors
- }
+export function parseCss(text) {
+ const lexResult = CssLexer.tokenize(text)
+ // setting a new input will RESET the parser instance's state.
+ parser.input = lexResult.tokens
+ // any top level rule may be used as an entry point
+ const cst = parser.stylesheet()
+
+ return {
+ cst: cst,
+ lexErrors: lexResult.errors,
+ parseErrors: parser.errors
  }
 }

examples/grammars/css/css_spec.js

@@ -1,5 +1,5 @@
-const assert = require("assert")
-const parseCss = require("./css").parseCss
+import assert from "assert"
+import { parseCss } from "./css.js"
 
 describe("The CSS Grammar", () => {
  it("can parse a simple CSS without errors", () => {

examples/grammars/csv/csv.js

@@ -1,12 +1,11 @@
-"use strict"
 /**
  * An Example of implementing a CSV Grammar with Chevrotain.
  *
  * Based on: https://github.com/antlr/grammars-v4/blob/master/csv/CSV.g4
  *
  * Note that this is a pure grammar without any actions (either embedded or via a CST Visitor).
  */
-const { createToken, Lexer, CstParser, EMPTY_ALT } = require("chevrotain")
+import { createToken, Lexer, CstParser, EMPTY_ALT } from "chevrotain"
 
 // ----------------- lexer -----------------
 const Text = createToken({ name: "Text", pattern: /[^,\n\r"]+/ })
@@ -67,7 +66,7 @@ class CsvParser extends CstParser {
 // reuse the same parser instance.
 const parser = new CsvParser([])
 
-module.exports = function (text) {
+export function parseCsv(text) {
  // 1. Tokenize the input.
  const lexResult = CsvLexer.tokenize(text)
 

examples/grammars/csv/csv_spec.js

@@ -1,9 +1,10 @@
-"use strict"
+import path from "path"
+import { fileURLToPath } from "url"
+import fs from "fs"
+import assert from "assert"
+import { parseCsv } from "./csv.js"
 
-const path = require("path")
-const fs = require("fs")
-const assert = require("assert")
-const parseCsv = require("./csv")
+const __dirname = path.dirname(fileURLToPath(import.meta.url))
 
 describe("The CSV Grammar", () => {
  const samplePath = path.resolve(__dirname, "./sample.csv")

examples/grammars/ecma5/ecma5_api.js

@@ -1,11 +1,9 @@
-"use strict"
-
-const tokenize = require("./ecma5_lexer").tokenize
-const ECMAScript5Parser = require("./ecma5_parser").ECMAScript5Parser
+import { tokenize } from "./ecma5_lexer.js"
+import { ECMAScript5Parser } from "./ecma5_parser.js"
 
 const parserInstance = new ECMAScript5Parser()
 
-function parse(str) {
+export function parse(str) {
  const tokens = tokenize(str)
  parserInstance.input = tokens
  parserInstance.orgText = str
@@ -15,7 +13,3 @@ function parse(str) {
  throw Error("Sad Sad Panda")
  }
 }
-
-module.exports = {
- parse
-}

examples/grammars/ecma5/ecma5_lexer.js

@@ -1,5 +1,3 @@
-"use strict"
-
 /**
  * ECMAScript cannot be easily lexed using a distinct lexing phase.
  * See: https://users.soe.ucsc.edu/~cormac/papers/dls14a.pdf
@@ -11,9 +9,9 @@
  * https://github.com/chevrotain/chevrotain/blob/master/test/full_flow/ecma_quirks/ecma_quirks.ts
  *
  */
-const acorn = require("acorn")
+import * as acorn from "acorn"
 const acornTokTypes = acorn.tokTypes
-const tokens = require("./ecma5_tokens")
+import * as tokens from "./ecma5_tokens.js"
 
 function createChevToken(chevTokenClass, acornToken) {
  return {
@@ -24,7 +22,7 @@ function createChevToken(chevTokenClass, acornToken) {
  }
 }
 
-function tokenize(str) {
+export function tokenize(str) {
  const result = []
  for (let token of acorn.tokenizer(str, { ecmaVersion: 6 })) {
  let acornType = token.type
@@ -325,7 +323,3 @@ function tokenize(str) {
 
  return result
 }
-
-module.exports = {
- tokenize
-}

examples/grammars/ecma5/ecma5_parser.js

@@ -1,26 +1,22 @@
-"use strict"
-
-const {
+import {
  EmbeddedActionsParser,
  EOF,
  tokenMatcher,
  MismatchedTokenException
-} = require("chevrotain")
-const tokens = require("./ecma5_tokens")
-// for conciseness
-const t = tokens
+} from "chevrotain"
+import * as t from "./ecma5_tokens.js"
 
 const ENABLE_SEMICOLON_INSERTION = true
 const DISABLE_SEMICOLON_INSERTION = false
 
 // as defined in https://www.ecma-international.org/ecma-262/5.1/index.html
-class ECMAScript5Parser extends EmbeddedActionsParser {
+export class ECMAScript5Parser extends EmbeddedActionsParser {
  set orgText(newText) {
  this._orgText = newText
  }
 
  constructor() {
- super(tokens, {
+ super(t, {
  // Reduces Parser Initialization time and this grammar does not need
  // a larger lookahead.
  maxLookahead: 2
@@ -905,7 +901,3 @@ const insertedSemiColon = {
  endOffset: NaN,
  automaticallyInserted: true
 }
-
-module.exports = {
- ECMAScript5Parser
-}

examples/grammars/ecma5/ecma5_spec.js

@@ -1,7 +1,6 @@
-"use strict"
+import { expect } from "chai"
 
-const expect = require("chai").expect
-const parse = require("./ecma5_api").parse
+import { parse } from "./ecma5_api.js"
 
 describe("The ECMAScript5 Grammar", () => {
  const sampleText = `var chevrotain = require("chevrotain")