Type of 'yield' operand in an async generator must either be a valid promise ...
Production Risk
Build will fail; resolve before shipping.
A syntax error (TS1321): Type of 'yield' operand in an async generator must either be a valid promise or must not contain a callable 'then' member.. This diagnostic is emitted by the TypeScript compiler when type of 'yield' operand in an async generator must either be a valid promise or must not contain a callable 'then' member..
- 1await used outside an async function, or async/await return type mismatch
TypeScript compiler reports TS1321 during type checking.
// Triggers TS1321 // Type of 'yield' operand in an async generator must either be a valid promise or must not contain a callable 'then' member.
expected output
error TS1321: Type of 'yield' operand in an async generator must either be a valid promise or must not contain a callable 'then' member.
Fix
Address the TypeScript diagnostic
WHEN When this error is reported by the compiler
// 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.
TypeScript Compiler Diagnostics
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