constraint causes too specific generic type inference

[marcospgp]

🔎 Search Terms

I'm writing a generic function:

export function useKeyValueStore<T extends string | number | boolean>(
  key: string,
  initialValue: T,
): [T, (value: T) => void] {

if I call it with useKeyValueStore("someKey", 100), T gets inferred as 100

if I remove the extends string | number | boolean type constraint, it gets inferred as number

this seems like unintended behavior - I'd like to keep the constraint and infer T as number

🕗 Version & Regression Information

• This changed between versions ______ and _______
• This changed in commit or PR _______
• This is the behavior in every version I tried, and I reviewed the FAQ for entries about _________
• I was unable to test this on prior versions because _______

⏯ Playground Link

No response

💻 Code

// Your code here

🙁 Actual behavior

see above

🙂 Expected behavior

see above

Additional information about the issue

No response

[RyanCavanaugh]

This behavior is intentional. If you want the other behavior, you can write

export function useKeyValueStore<T>(key: string, initialValue: T & (string | number | boolean)): [T, (value: T) => void]

[typescript-bot]

This issue has been marked as "Not a Defect" and has seen no recent activity. It has been automatically closed for house-keeping purposes.