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Parsing error: The keyword 'interface' is reserved

Time:12-01

I am creating a NodeJS and MongoDB library for CRUD operations on APIs. I am trying to create an interface with Typescript for the url and database name, as follows:

but I get the following error:

interface IConfig {
  url: string
  name: string
}

export default IConfig

Parsing error: The keyword 'interface' is reserved

I am using standardjs as a linter, and this is my tsconfig file:

{
  "compilerOptions": {
    /* Visit https://aka.ms/tsconfig.json to read more about this file */

    /* Projects */
    // "incremental": true,                              /* Enable incremental compilation */
    // "composite": true,                                /* Enable constraints that allow a TypeScript project to be used with project references. */
    // "tsBuildInfoFile": "./",                          /* Specify the folder for .tsbuildinfo incremental compilation files. */
    // "disableSourceOfProjectReferenceRedirect": true,  /* Disable preferring source files instead of declaration files when referencing composite projects */
    // "disableSolutionSearching": true,                 /* Opt a project out of multi-project reference checking when editing. */
    // "disableReferencedProjectLoad": true,             /* Reduce the number of projects loaded automatically by TypeScript. */

    /* Language and Environment */
    "target": "es2020",                                  /* Set the JavaScript language version for emitted JavaScript and include compatible library declarations. */
    // "lib": [],                                        /* Specify a set of bundled library declaration files that describe the target runtime environment. */
    // "jsx": "preserve",                                /* Specify what JSX code is generated. */
    "experimentalDecorators": true,                   /* Enable experimental support for TC39 stage 2 draft decorators. */
    "emitDecoratorMetadata": true,                    /* Emit design-type metadata for decorated declarations in source files. */
    // "jsxFactory": "",                                 /* Specify the JSX factory function used when targeting React JSX emit, e.g. 'React.createElement' or 'h' */
    // "jsxFragmentFactory": "",                         /* Specify the JSX Fragment reference used for fragments when targeting React JSX emit e.g. 'React.Fragment' or 'Fragment'. */
    // "jsxImportSource": "",                            /* Specify module specifier used to import the JSX factory functions when using `jsx: react-jsx*`.` */
    // "reactNamespace": "",                             /* Specify the object invoked for `createElement`. This only applies when targeting `react` JSX emit. */
    // "noLib": true,                                    /* Disable including any library files, including the default lib.d.ts. */
    // "useDefineForClassFields": true,                  /* Emit ECMAScript-standard-compliant class fields. */

    /* Modules */
    "module": "commonjs",                                /* Specify what module code is generated. */
    // "rootDir": "./src",                                  /* Specify the root folder within your source files. */
    // "moduleResolution": "node",                       /* Specify how TypeScript looks up a file from a given module specifier. */
    // "baseUrl": "./",                                  /* Specify the base directory to resolve non-relative module names. */
    // "paths": {},                                      /* Specify a set of entries that re-map imports to additional lookup locations. */
    // "rootDirs": [],                                   /* Allow multiple folders to be treated as one when resolving modules. */
    // "typeRoots": [],                                  /* Specify multiple folders that act like `./node_modules/@types`. */
    // "types": [],                                      /* Specify type package names to be included without being referenced in a source file. */
    // "allowUmdGlobalAccess": true,                     /* Allow accessing UMD globals from modules. */
    // "resolveJsonModule": true,                        /* Enable importing .json files */
    // "noResolve": true,                                /* Disallow `import`s, `require`s or `<reference>`s from expanding the number of files TypeScript should add to a project. */

    /* JavaScript Support */
    // "allowJs": true,                                  /* Allow JavaScript files to be a part of your program. Use the `checkJS` option to get errors from these files. */
    // "checkJs": true,                                  /* Enable error reporting in type-checked JavaScript files. */
    // "maxNodeModuleJsDepth": 1,                        /* Specify the maximum folder depth used for checking JavaScript files from `node_modules`. Only applicable with `allowJs`. */

    /* Emit */
    "declaration": true,                              /* Generate .d.ts files from TypeScript and JavaScript files in your project. */
    "declarationMap": true,                           /* Create sourcemaps for d.ts files. */
    // "emitDeclarationOnly": true,                      /* Only output d.ts files and not JavaScript files. */
    "sourceMap": true,                                /* Create source map files for emitted JavaScript files. */
    // "outFile": "./",                                  /* Specify a file that bundles all outputs into one JavaScript file. If `declaration` is true, also designates a file that bundles all .d.ts output. */
    "outDir": "./lib",                                   /* Specify an output folder for all emitted files. */
    // "removeComments": true,                           /* Disable emitting comments. */
    // "noEmit": true,                                   /* Disable emitting files from a compilation. */
    // "importHelpers": true,                            /* Allow importing helper functions from tslib once per project, instead of including them per-file. */
    // "importsNotUsedAsValues": "remove",               /* Specify emit/checking behavior for imports that are only used for types */
    // "downlevelIteration": true,                       /* Emit more compliant, but verbose and less performant JavaScript for iteration. */
    // "sourceRoot": "",                                 /* Specify the root path for debuggers to find the reference source code. */
    // "mapRoot": "",                                    /* Specify the location where debugger should locate map files instead of generated locations. */
    // "inlineSourceMap": true,                          /* Include sourcemap files inside the emitted JavaScript. */
    // "inlineSources": true,                            /* Include source code in the sourcemaps inside the emitted JavaScript. */
    // "emitBOM": true,                                  /* Emit a UTF-8 Byte Order Mark (BOM) in the beginning of output files. */
    // "newLine": "crlf",                                /* Set the newline character for emitting files. */
    // "stripInternal": true,                            /* Disable emitting declarations that have `@internal` in their JSDoc comments. */
    // "noEmitHelpers": true,                            /* Disable generating custom helper functions like `__extends` in compiled output. */
    // "noEmitOnError": true,                            /* Disable emitting files if any type checking errors are reported. */
    // "preserveConstEnums": true,                       /* Disable erasing `const enum` declarations in generated code. */
    // "declarationDir": "./",                           /* Specify the output directory for generated declaration files. */
    // "preserveValueImports": true,                     /* Preserve unused imported values in the JavaScript output that would otherwise be removed. */

    /* Interop Constraints */
    // "isolatedModules": true,                          /* Ensure that each file can be safely transpiled without relying on other imports. */
    // "allowSyntheticDefaultImports": true,             /* Allow 'import x from y' when a module doesn't have a default export. */
    "esModuleInterop": true,                             /* Emit additional JavaScript to ease support for importing CommonJS modules. This enables `allowSyntheticDefaultImports` for type compatibility. */
    // "preserveSymlinks": true,                         /* Disable resolving symlinks to their realpath. This correlates to the same flag in node. */
    "forceConsistentCasingInFileNames": true,            /* Ensure that casing is correct in imports. */

    /* Type Checking */
    "strict": true,                                      /* Enable all strict type-checking options. */
    "noImplicitAny": true,                            /* Enable error reporting for expressions and declarations with an implied `any` type.. */
    "strictNullChecks": true,                         /* When type checking, take into account `null` and `undefined`. */
    "strictFunctionTypes": true,                      /* When assigning functions, check to ensure parameters and the return values are subtype-compatible. */
    "strictBindCallApply": true,                      /* Check that the arguments for `bind`, `call`, and `apply` methods match the original function. */
    "strictPropertyInitialization": true,             /* Check for class properties that are declared but not set in the constructor. */
    "noImplicitThis": true,                           /* Enable error reporting when `this` is given the type `any`. */
    "useUnknownInCatchVariables": true,               /* Type catch clause variables as 'unknown' instead of 'any'. */
    "alwaysStrict": true,                             /* Ensure 'use strict' is always emitted. */
    "noUnusedLocals": true,                           /* Enable error reporting when a local variables aren't read. */
    "noUnusedParameters": true,                       /* Raise an error when a function parameter isn't read */
    "exactOptionalPropertyTypes": true,               /* Interpret optional property types as written, rather than adding 'undefined'. */
    "noImplicitReturns": true,                        /* Enable error reporting for codepaths that do not explicitly return in a function. */
    "noFallthroughCasesInSwitch": true,               /* Enable error reporting for fallthrough cases in switch statements. */
    "noUncheckedIndexedAccess": true,                 /* Include 'undefined' in index signature results */
    "noImplicitOverride": true,                       /* Ensure overriding members in derived classes are marked with an override modifier. */
    "noPropertyAccessFromIndexSignature": true,       /* Enforces using indexed accessors for keys declared using an indexed type */
    // "allowUnusedLabels": true,                        /* Disable error reporting for unused labels. */
    // "allowUnreachableCode": true,                     /* Disable error reporting for unreachable code. */

    /* Completeness */
    // "skipDefaultLibCheck": true,                      /* Skip type checking .d.ts files that are included with TypeScript. */
    "skipLibCheck": true                                 /* Skip type checking all .d.ts files. */
  }
}

Let me show you what dependencies I have already. I am using babel because jest required for compilation:

  "devDependencies": {
    "@babel/core": "~7.16.0",
    "@babel/preset-env": "~7.16.4",
    "@babel/preset-typescript": "~7.16.0",
    "@types/jest": "~27.0.3",
    "@types/mongodb": "^4.0.7",
    "@typescript-eslint/eslint-plugin": "^5.4.0",
    "@typescript-eslint/parser": "^5.4.0",
    "eslint": "^8.3.0",
    "eslint-plugin-jest": "^25.3.0",
    "jest": "~27.4.0",
    "standard": "~16.0.4",
    "test-jest": "~1.0.1",
    "ts-node": "~10.4.0"
  },
  "dependencies": {
    "mongodb": "~4.2.0",
    "typescript": "~4.5.2"
  },

I am sure is any error in my configuration, can you take a look and help me?

CodePudding user response:

You should reconfigure your standardjs to use ts-standard instead.

interface is a "future reserved keyword" in Javascript. Javascript disallows its use as an identifier so that it can be used as a keyword (as it is in TypeScript). The TypeScript compiler removes the interface definition so it doesn't appear in the compiled Javascript output.

From the standardjs front page FAQs:

standard supports the latest ECMAScript features. However, Flow and TypeScript add new syntax to the language, so they are not supported out-of-the-box.

For TypeScript, an official variant ts-standard is supported and maintained that provides a very similar experience to standard.

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