TS4099
TypeScriptERRORNotableDeclarationHIGH confidence
Public method 'X' of exported class has or is using name 'X' from private mod...
Production Risk
Build will fail; resolve before shipping.
What this means
A declaration emit error (TS4099): Public method 'X' of exported class has or is using name 'X' from private module 'X'.. This diagnostic is emitted by the TypeScript compiler when public method 'X' of exported class has or is using name 'X' from private module 'X'..
Why it happens
- 1Incorrect TypeScript syntax or type usage
- 2Type mismatch between declared and actual value
How to reproduce
TypeScript compiler reports TS4099 during type checking.
trigger — this will error
trigger — this will error
// Triggers TS4099 // Public method 'X' of exported class has or is using name 'X' from private module 'X'.
expected output
error TS4099: Public method 'X' of exported class has or is using name 'X' from private module '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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