Generic function with two or more types cannot infer type provided as function parameter

[HaukeSchnau]

Bug Report

🔎 Search Terms

• infer generic type
• multiple type parameters

🕗 Version & Regression Information

• This is the behavior in every version I tried, and I reviewed the FAQ for entries about generics

⏯ Playground Link

Playground link with relevant code

💻 Code

const doSomething = <B,>(argB: B) => {};
doSomething("foo"); // Works as expected

const doSomethingElse = <A, B>(argB: B) => {};
doSomethingElse<"bar">("foo"); // Error: Expected 2 type arguments, but got 1

🙁 Actual behavior

TypeScript throws an error in the second example despite being able to infer the type in the first one

🙂 Expected behavior

No error, TypeScript infers the second type as "foo", since it is provided as an parameter

[MartinJohns]

This is working as intended / a design limitation. Type argument inference is all or nothing. You want #26242 / #26349.

[HaukeSchnau]

Alright, thanks for the heads up :)
Will follow the issue and PR