Is it possible to enforce a strict return type in TypeScript? For example, if I have the following code:
function codeToMsg(a: number): string {
if (a == 200)
return "OK";
}
let msg = codeToMsg(123456);
The compiler does not throw an error even though the function may not always return a value of type string. How can we ensure this is enforced?
To trigger an error, enable either the strictNullChecks or noImplicitReturns compiler options.
You can consider enabling the option "noImplicitReturns": true to receive a warning when not all code paths return a value.
Alternatively, you could opt for strictNullCheck, but be aware that this will lead your function to generate an error along with some undesirable side effects.
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