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geon/tsbug.ts

Last active November 20, 2017 14:50
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tsbug.ts
console.log(myFunction());
const myConstant = "";
function myFunction(myArgument: string = myConstant): string {
return myArgument;
}
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geon commented Nov 20, 2017

You would expect myFunction to return a string, since it is typed as such. But it returns undefined.

This comes from the default value myConstant not being defined at the point where the function is called. This should either be an error (preferably), or myArgument should be forced to be typed to string | undefined (weird).

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