Function strip

test/utils.ts:281–309

(expr: Expression)

  if (typeof expr === 'number') return expr;
  if (typeof expr === 'string') {
    if (expr[0] === "'" && expr[expr.length - 1] === "'") {
      return { str: expr.slice(1, -1) };
    }
    return expr;
  }
  if (Array.isArray(expr))
    return expr.map(
      (x) => strip(x ?? 'Nothing') ?? 'Nothing'
    ) as any as Expression;

  if (typeof expr === 'object') {
    if ('num' in expr) return validJSONNumber(expr.num);
    if ('sym' in expr) return expr.sym;
    if ('fn' in expr) {
      return expr.fn.map(
        (x) => strip(x ?? 'Nothing') ?? 'Nothing'
      ) as any as Expression;
    }

    if ('str' in expr) return { str: expr.str };

    console.log('Unexpected object literal as an Expression');
  }

  return null;
}

function formatError(errors: ParsingDiagnostic[]): Expression {
  return [
    'Error',
    [
      'String',