@bablr/language-en-es6/lib/mixins/class.macro.js

A BABLR language for ES6 (JavaScript)

import { spam as m } from '@bablr/boot';
import { CoveredBy, Node } from '@bablr/helpers/decorators';
import { o, eat, eatMatch, fail } from '@bablr/helpers/grammar';

export const mixin = (Base) =>
  class ES6ClassGrammar extends Base {
    @Node
    *ClassDeclaration() {
      yield eat(m`sigilToken: <*Keyword 'class' />`);

      yield eat(m`name$: <Identifier />`);

      if (yield eatMatch(m`extendsToken: <*Keyword 'extends' />`, o({}), o({ bind: true }))) {
        yield eat(m`superClass$: <__Expression>`);
      } else {
        yield eat(m`superClass$: null`);
      }

      yield eat(m`body: <ClassBody />`);
    }

    @CoveredBy('Expression')
    @Node
    *ClassExpression() {
      yield eat(m`sigilToken: <*Keyword 'class' />`);

      yield eatMatch(m`name$: <Identifier />`);

      if (yield eatMatch(m`extendsToken: <*Keyword 'extends' />`)) {
        yield eat(m`superClass$: <__Expression>`);
      } else {
        yield eat(m`superClass$: null`);
      }

      yield eat(m`body: <ClassBody />`);
    }

    @Node
    *ClassBody() {
      yield eat(m`openToken: <*Punctuator '{' { balanced: '}' } />`);
      while (yield eatMatch(m`members[]: <__ClassMember />`)) {}
      yield eat(m`closeToken: <*Punctuator '}' { balancer: true } />`);
    }

    *ClassMember() {
      yield eat(m`<ClassMethod />`);
    }

    @CoveredBy('ClassMember')
    @Node
    *ClassMethod() {
      yield eatMatch(m`staticToken: <*Keyword 'static' />`);
      let acc, a, gen;
      acc = yield eatMatch(m`kindToken: <*Keyword /get|set/ />`);

      if (!acc) {
        a = yield eatMatch(m`asyncToken: <*Keyword 'async' />`);
        gen = yield eatMatch(m`starToken: <*Punctuator '*' />`);
      } else {
        yield eatMatch(m`asyncToken: null`);
        yield eatMatch(m`starToken: null`);
      }

      if (a && gen) yield fail();

      yield eatMatch(m`id: <Identifier />`, o({}), o({ bind: true }));

      yield eat(m`openParamsToken: <*Punctuator '(' { balanced: ')' } />`);
      yield eat(
        m`params[]: <_List />`,
        o({
          element: m`<Identifier />`,
          allowTrailingSeparator: false,
          separator: m`separatorTokens[]: <*Punctuator ',' />`,
        }),
      );
      yield eat(m`closeParamsToken: <*Punctuator ')' { balancer: true } />`);
      yield eat(m`body: <BlockStatement />`);
    }

    @CoveredBy('Expression')
    @Node
    *SuperExpression() {
      yield eat(m`sigilToken: <*Keyword 'super' />`);
    }

    @CoveredBy('Expression')
    @Node
    *ThisExpression() {
      yield eat(m`sigilToken: <*Keyword 'this' />`);
    }
  };