TS2503
TypeScriptERRORNotableTypeHIGH confidence
Cannot find namespace 'X'.
Production Risk
Build will fail; resolve before shipping.
What this means
A type-checking error (TS2503): Cannot find namespace 'X'.. This diagnostic is emitted by the TypeScript compiler when cannot find namespace 'X'..
Why it happens
- 1The variable, type, or namespace is not declared in scope
- 2A missing import or type declaration
How to reproduce
TypeScript compiler reports TS2503 during type checking.
trigger — this will error
trigger — this will error
// Triggers TS2503 // Cannot find namespace 'X'.
expected output
error TS2503: Cannot find namespace 'X'.
Fix
Declare or import the missing name
WHEN When a variable or type is not in scope
Declare or import the missing name
// Add the missing import
import { MyType } from './my-module';
// Or declare the variable
const myVar: MyType = ...;Why this works
TypeScript requires all names to be declared before use; add the missing declaration or import.
Sources
Official documentation ↗
TypeScript Compiler Diagnostics
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