Error map

TS2349: This expression is not callable TypeScript: error TS2349: This expression is not callable. Type 'X' has no call signatures.

TypeScript · layer 1, On your device

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Centre: this error. First ring: errors it is linked with (9). Outer ring: what those are linked with. Colours show the layer of a request each error belongs to. Click any dot to re-centre the map on it; hover to follow its connections. The centre dot opens the error page.

TS2349: This expression is not callable — TypeScript: error TS2349: This expression is not callable. Type 'X' has no call signatures. (TypeScript)TS2349: Thi…TS2366: Function lacks ending return statement — TypeScript: error TS2366: Function lacks ending return statement and return type does not include 'undefined'. (TypeScript)TS2366: Function la…TS1259: Module can only be default-imported using the 'esModuleInterop' flag — TypeScript: error TS1259: Module '"express"' can only be default-imported using the 'esModuleInterop' flag (TypeScript)TS1259: Module can …TS2393: Duplicate function implementation — TypeScript: error TS2393: Duplicate function implementation. (TypeScript)TS2393: Duplicate f…TS2554: Expected N arguments, but got M — TypeScript: error TS2554: Expected 2 arguments, but got 1. (TypeScript)TS2554: Expected N …TS2604: JSX element type does not have any construct or call signatures — TypeScript: error TS2604: JSX element type 'Foo' does not have any construct or call signatures. (TypeScript)TS2604: JSX element…TS2693: 'X' only refers to a type, but is being used as a value here — TypeScript: error TS2693: 'User' only refers to a type, but is being used as a value here. (TypeScript)TS2693: 'X' only re…TS2769: No overload matches this call — TypeScript: error TS2769: No overload matches this call. Overload 1 of 2, '(a: string): void', gave the following error. (TypeScript)TS2769: No overload…TS1005: ';' expected / ',' expected (syntax error) — TypeScript: error TS1005: ';' expected. (TypeScript)TS1005: ';' expecte…Cannot find module './App.vue' or its corresponding type declarations — TypeScript: error TS2307: Cannot find module './App.vue' or its corresponding type declarations. (Vue)Cannot find module …TS2322 — TS2322: Type 'X' is not assignable to type 'Y' (TypeScript)TS2322TS2367: This comparison appears to be unintentional — TypeScript: error TS2367: This comparison appears to be unintentional because the types '"a" | "b"' and '"c"' have no overlap. (TypeScript)TS2367: This compar…TS2454: Variable is used before being assigned — TypeScript: error TS2454: Variable 'x' is used before being assigned. (TypeScript)TS2454: Variable is…ERR_REQUIRE_ESM — Error [ERR_REQUIRE_ESM]: require() of ES Module not supported (Node.js)ERR_REQUIRE_ESMSyntaxError import — SyntaxError: Cannot use import statement outside a module (Node.js)SyntaxError importERR_IMPORT_ATTRIBUTE_MISSING — TypeError [ERR_IMPORT_ATTRIBUTE_MISSING]: Module needs an import attribute of "type: json" (Node.js)ERR_IMPORT_ATTRIBUT…TS2300: Duplicate identifier — TypeScript: error TS2300: Duplicate identifier 'Foo'. (TypeScript)TS2300: Duplicate i…TS2451: Cannot redeclare block-scoped variable — TypeScript: error TS2451: Cannot redeclare block-scoped variable 'name'. (TypeScript)TS2451: Cannot rede…TS2345 — TS2345: Argument of type 'string | undefined' is not assignable to parameter of type 'string'. (Node.js)TS2345TS1128: Declaration or statement expected — TypeScript: error TS1128: Declaration or statement expected. (TypeScript)TS1128: Declaration…Objects are not valid as a React child — Error: Objects are not valid as a React child (React)Objects are not val…Nothing was returned from render — Error: Nothing was returned from render. This usually means a return statement is missing. (React)Nothing was returne…React must be in scope — ReferenceError: React is not defined / 'React' must be in scope when using JSX (React)React must be in sc…TS2304 — TS2304: Cannot find name 'x'. (Node.js)TS2304TS1192: Module has no default export — TypeScript: error TS1192: Module '"./utils"' has no default export. (TypeScript)TS1192: Module has …TS1208: File cannot be compiled under '--isolatedModules' because it is considered a global script file — TypeScript: error TS1208: 'index.ts' cannot be compiled under '--isolatedModules' because it is considered a global script file. Add an import, export, or an empty 'export {}' statement (TypeScript)TS1208: File cannot…TS2589: Type instantiation is excessively deep and possibly infinite — TypeScript: error TS2589: Type instantiation is excessively deep and possibly infinite. (TypeScript)TS2589: Type instan…Unexpected token < — SyntaxError: Unexpected token '<' (HTML served instead of JavaScript) (JavaScript)Unexpected token <unexpected end of input — SyntaxError: Unexpected end of input (JavaScript)unexpected end of i…missing ) — SyntaxError: missing ) after argument list (JavaScript)missing )ERR_UNKNOWN_FILE_EXTENSION — TypeError [ERR_UNKNOWN_FILE_EXTENSION]: Unknown file extension ".ts" (Node.js)ERR_UNKNOWN_FILE_EX…TS2307 — TS2307: Cannot find module 'x' or its corresponding type declarations. (Node.js)TS2307TS7016 — TS7016: Could not find a declaration file for module 'x'. 'x.js' implicitly has an 'any' type. (Node.js)TS7016

Directly related (9)

TS2366: Function lacks ending return statementTypeScript

TypeScript: error TS2366: Function lacks ending return statement and return type does not include 'undefined'.

A function with a declared return type can reach its end without returning on some path.

TS1259: Module can only be default-imported using the 'esModuleInterop' flagTypeScript

TypeScript: error TS1259: Module '"express"' can only be default-imported using the 'esModuleInterop' flag

You default-import a CommonJS module that uses `export =`, but `esModuleInterop` isn't enabled.

TS2393: Duplicate function implementationTypeScript

TypeScript: error TS2393: Duplicate function implementation.

A function with the same name/signature is implemented more than once in the same scope.

TS2554: Expected N arguments, but got MTypeScript

TypeScript: error TS2554: Expected 2 arguments, but got 1.

A call passes too few or too many arguments.

TS2604: JSX element type does not have any construct or call signaturesTypeScript

TypeScript: error TS2604: JSX element type 'Foo' does not have any construct or call signatures.

You used something as a JSX component that TypeScript doesn't see as a component (not a function/class returning JSX).

TS2693: 'X' only refers to a type, but is being used as a value hereTypeScript

TypeScript: error TS2693: 'User' only refers to a type, but is being used as a value here.

You used an interface/type alias where a runtime value is needed.

TS2769: No overload matches this callTypeScript

TypeScript: error TS2769: No overload matches this call. Overload 1 of 2, '(a: string): void', gave the following error.

A call matched none of the function's overload signatures.

TS1005: ';' expected / ',' expected (syntax error)TypeScript

TypeScript: error TS1005: ';' expected.

The parser hit a syntax error — missing punctuation, mismatched brackets, or an unsupported syntax for your TypeScript version.

Cannot find module './App.vue' or its corresponding type declarationsVue

TypeScript: error TS2307: Cannot find module './App.vue' or its corresponding type declarations.

TypeScript doesn't know what a `.vue` import is without a shim or Volar/`vue-tsc`.

Two steps away (23)

TS2322TypeScript

TS2322: Type 'X' is not assignable to type 'Y'

You assigned a value whose type doesn’t match the declared type of the variable, property or return value.

TS2367: This comparison appears to be unintentionalTypeScript

TypeScript: error TS2367: This comparison appears to be unintentional because the types '"a" | "b"' and '"c"' have no overlap.

You compare two values whose types can never be equal.

TS2454: Variable is used before being assignedTypeScript

TypeScript: error TS2454: Variable 'x' is used before being assigned.

Control flow shows a path where the variable is read before any assignment.

ERR_REQUIRE_ESMNode.js

Error [ERR_REQUIRE_ESM]: require() of ES Module not supported

CommonJS code used `require()` on a package that is ES-module-only (node-fetch 3, chalk 5, nanoid 4, got 12…).

SyntaxError importNode.js

SyntaxError: Cannot use import statement outside a module

An `import` statement ran in a context treated as CommonJS (Node without "type": "module", a browser script without type="module"…

ERR_IMPORT_ATTRIBUTE_MISSINGNode.js

TypeError [ERR_IMPORT_ATTRIBUTE_MISSING]: Module needs an import attribute of "type: json"

An ES module imported a .json file without the required import attribute.

TS2300: Duplicate identifierTypeScript

TypeScript: error TS2300: Duplicate identifier 'Foo'.

The same name is declared twice in the same scope (or in merged global declarations).

TS2451: Cannot redeclare block-scoped variableTypeScript

TypeScript: error TS2451: Cannot redeclare block-scoped variable 'name'.

A `let`/`const`/`class` name was declared twice in the same scope — often because files are global scripts sharing one scope.

TS2345Node.js

TS2345: Argument of type 'string | undefined' is not assignable to parameter of type 'string'.

A value’s type doesn’t match the function parameter — commonly a possibly-undefined value passed where a definite one is required.

TS1128: Declaration or statement expectedTypeScript

TypeScript: error TS1128: Declaration or statement expected.

The parser found a token where a declaration or statement should start — usually stray braces/parentheses or code outside a funct…

Objects are not valid as a React childReact

Error: Objects are not valid as a React child

You tried to render a plain object (or a Promise/Date) directly in JSX; React can only render strings, numbers, elements and arra…

Nothing was returned from renderReact

Error: Nothing was returned from render. This usually means a return statement is missing.

A component returned undefined (React 17 and earlier) — usually a missing return or a return followed by a line break.

React must be in scopeReact

ReferenceError: React is not defined / 'React' must be in scope when using JSX

JSX was compiled with the classic runtime, which needs React imported in every file.

TS2304Node.js

TS2304: Cannot find name 'x'.

TypeScript doesn’t know an identifier — a missing import, missing type definitions (e.g. for Node or Jest globals), or a typo.

TS1192: Module has no default exportTypeScript

TypeScript: error TS1192: Module '"./utils"' has no default export.

You used `import x from "./mod"` but the module only has named exports.

TS1208: File cannot be compiled under '--isolatedModules' because it is considered a global script fileTypeScript

TypeScript: error TS1208: 'index.ts' cannot be compiled under '--isolatedModules' because it is considered a global script file. Add an import, export, or an empty 'export {}' statement

With `isolatedModules`, every file must be a module (have an import or export).

TS2589: Type instantiation is excessively deep and possibly infiniteTypeScript

TypeScript: error TS2589: Type instantiation is excessively deep and possibly infinite.

The compiler hit its recursion limit while evaluating a very complex or recursive generic type.

Unexpected token <JavaScript

SyntaxError: Unexpected token '<' (HTML served instead of JavaScript)

The browser loaded a .js file but received HTML (an error page or the SPA index.html).

unexpected end of inputJavaScript

SyntaxError: Unexpected end of input

The parser reached the end of the code (or JSON) while still expecting more — a missing } ) ] or empty JSON.

missing )JavaScript

SyntaxError: missing ) after argument list

A function call’s parentheses are unbalanced — often an unescaped quote or a missing comma/plus.

ERR_UNKNOWN_FILE_EXTENSIONNode.js

TypeError [ERR_UNKNOWN_FILE_EXTENSION]: Unknown file extension ".ts"

Node tried to run a TypeScript file as ESM without a TypeScript loader.

TS2307Node.js

TS2307: Cannot find module 'x' or its corresponding type declarations.

TypeScript can’t resolve the import — the package isn’t installed, the path alias isn’t configured, or there are no types.

TS7016Node.js

TS7016: Could not find a declaration file for module 'x'. 'x.js' implicitly has an 'any' type.

The JavaScript package has no TypeScript types bundled and no @types package installed.