Function parseBasic2

book/tiny-ts-parser.ts:1079–1121

(code: string)

}

export function parseBasic2(code: string): TermForBasic2 {
  function conv(node: Term): Term {
    switch (node.tag) {
      case "if":
        return { tag: "if", cond: conv(node.cond), thn: conv(node.thn), els: conv(node.els), loc: node.loc };
      case "add":
        return { tag: "add", left: conv(node.left), right: conv(node.right), loc: node.loc };
      case "func":
        return { tag: "func", params: node.params, body: conv(node.body), loc: node.loc };
      case "call":
        return { tag: "call", func: conv(node.func), args: node.args.map(conv), loc: node.loc };
      case "seq":
      case "const": {
        const body: Term[] = [];
        while (true) {
          switch (node.tag) {
            case "seq": {
              body.push(conv(node.body));
              node = node.rest;
              break;
            }
            case "const": {
              body.push({ tag: "const2", name: node.name, init: conv(node.init), loc: node.loc });
              node = node.rest;
              break;
            }
            default: {
              body.push(conv(node));
              return { tag: "seq2", body, loc: node.loc };
            }
          }
        }
      }
      default:
        return node;
    }
  }
  return subsetSystem(
    conv(parse(code)),
    ["Boolean", "Number", "Func"],
    ["true", "false", "if", "number", "add", "var", "func", "call", "seq2", "const2"],
  );
}

export function parseObj(code: string): TermForObj {
  return subsetSystem(