How to assign Typescript function signature to named functions?

When using typescript, I tend to write my functions in this pattern:

const myFunc: MyFuncType = (input, otherInput, moreInput) => {
  return input + otherInput + moreInput;
};

However, I can't seem to figure out how to pass an interface to a named function.

I'd like to do something like this:

function myFunc<MyFuncType>(input, otherInput, moreInput) {
  return input + otherInput + moreInput;
}

In that second example, Typescript assigns any to all my function parameters, instead of inferring the type of each parameter. Is the const pattern the only way to assign a function signature?

Thanks.