TS9029
TypeScriptERRORNotableTypeHIGH confidence
Add a type annotation to the property X.
Production Risk
Build will fail; resolve before shipping.
What this means
A TypeScript diagnostic (TS9029): Add a type annotation to the property X.. This diagnostic is emitted by the TypeScript compiler when add a type annotation to the property X..
Why it happens
- 1Incorrect TypeScript syntax or type usage
- 2Type mismatch between declared and actual value
How to reproduce
TypeScript compiler reports TS9029 during type checking.
trigger — this will error
trigger — this will error
// Triggers TS9029 // Add a type annotation to the property X.
expected output
error TS9029: Add a type annotation to the property X.
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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