TS2212
TypeScriptERRORNotableTypeHIGH confidence

Add `extends` constraint to all type parameters

Production Risk

Build will fail; resolve before shipping.

What this means

A type-checking error (TS2212): Add `extends` constraint to all type parameters. This diagnostic is emitted by the TypeScript compiler when add `extends` constraint to all type parameters.

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

TypeScript compiler reports TS2212 during type checking.

trigger — this will error
trigger — this will error
// Triggers TS2212
// Add `extends` constraint to all type parameters

expected output

error TS2212: Add `extends` constraint to all 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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