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import BuiltInRules from '../dist/built-in-rules.js';import {Builder} from '../src/Builder.js';import {Failure} from '../src/Failure.js';import {TerminalNode} from '../src/nodes.js';import * as pexprs from '../src/pexprs.js';import {findIndentation} from './findIndentation.js';import {InputStream} from './InputStream.js';
const INDENT_DESCRIPTION = 'an indented block';const DEDENT_DESCRIPTION = 'a dedent';
// A sentinel value that is out of range for both charCodeAt() and codePointAt().const INVALID_CODE_POINT = 0x10ffff + 1;
class InputStreamWithIndentation extends InputStream {  constructor(state) {    super(state.input);    this.state = state;  }
  _indentationAt(pos) {    return this.state.userData[pos] || 0;  }
  atEnd() {    return super.atEnd() && this._indentationAt(this.pos) === 0;  }
  next() {    if (this._indentationAt(this.pos) !== 0) {      this.examinedLength = Math.max(this.examinedLength, this.pos);      return undefined;    }    return super.next();  }
  nextCharCode() {    if (this._indentationAt(this.pos) !== 0) {      this.examinedLength = Math.max(this.examinedLength, this.pos);      return INVALID_CODE_POINT;    }    return super.nextCharCode();  }
  nextCodePoint() {    if (this._indentationAt(this.pos) !== 0) {      this.examinedLength = Math.max(this.examinedLength, this.pos);      return INVALID_CODE_POINT;    }    return super.nextCodePoint();  }}
class Indentation extends pexprs.PExpr {  constructor(isIndent = true) {    super();    this.isIndent = isIndent;  }
  allowsSkippingPrecedingSpace() {    return true;  }
  eval(state) {    const {inputStream} = state;    const pseudoTokens = state.userData;    state.doNotMemoize = true;
    const origPos = inputStream.pos;
    const sign = this.isIndent ? 1 : -1;    const count = (pseudoTokens[origPos] || 0) * sign;    if (count > 0) {      // Update the count to consume the pseudotoken.      state.userData = Object.create(pseudoTokens);      state.userData[origPos] -= sign;
      state.pushBinding(new TerminalNode(0), origPos);      return true;    } else {      state.processFailure(origPos, this);      return false;    }  }
  getArity() {    return 1;  }
  _assertAllApplicationsAreValid(ruleName, grammar) {}
  _isNullable(grammar, memo) {    return false;  }
  assertChoicesHaveUniformArity(ruleName) {}
  assertIteratedExprsAreNotNullable(grammar) {}
  introduceParams(formals) {    return this;  }
  substituteParams(actuals) {    return this;  }
  toString() {    return this.isIndent ? 'indent' : 'dedent';  }
  toDisplayString() {    return this.toString();  }
  toFailure(grammar) {    const description = this.isIndent ? INDENT_DESCRIPTION : DEDENT_DESCRIPTION;    return new Failure(this, description, 'description');  }}
// Create a new definition for `any` that can consume indent & dedent.const applyIndent = new pexprs.Apply('indent');const applyDedent = new pexprs.Apply('dedent');const newAnyBody = new pexprs.Splice(BuiltInRules, 'any', [applyIndent, applyDedent], []);
export const IndentationSensitive = new Builder()    .newGrammar('IndentationSensitive')    .withSuperGrammar(BuiltInRules)    .define('indent', [], new Indentation(true), INDENT_DESCRIPTION, undefined, true)    .define('dedent', [], new Indentation(false), DEDENT_DESCRIPTION, undefined, true)    .extend('any', [], newAnyBody, 'any character', undefined)    .build();
Object.assign(IndentationSensitive, {  _matchStateInitializer(state) {    state.userData = findIndentation(state.input);    state.inputStream = new InputStreamWithIndentation(state);  },  supportsIncrementalParsing: false,});