EC
TS2428
TypeScriptERRORNotableTypeHIGH confidence

All declarations of 'X' must have identical type parameters.

Production Risk

Build will fail; resolve before shipping.

What this means

A type-checking error (TS2428): All declarations of 'X' must have identical type parameters.. This diagnostic is emitted by the TypeScript compiler when all declarations of 'X' must have identical type parameters..

Why it happens
  1. 1Incorrect number or type of generic type arguments
How to reproduce

TypeScript compiler reports TS2428 during type checking.

trigger — this will error
trigger — this will error
// Triggers TS2428
// All declarations of 'X' must have identical type parameters.

expected output

error TS2428: All declarations of 'X' must have identical type parameters.

Fix

Address the TypeScript diagnostic

WHEN When this error is reported by the compiler

Address the TypeScript diagnostic
// Run the TypeScript compiler for details:
npx tsc --noEmit
// Use the TypeScript playground to test your code:
// https://www.typescriptlang.org/play

Why this works

Review the full error message and location; the TypeScript handbook provides guidance on each error category.

Sources
Official documentation ↗

TypeScript Compiler Diagnostics

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