Intrinsic/utility types, like TypeScript (feature request - mostly for function generics)

[LoganDark]

TypeScript has types/aliases like Parameters<...> which accept a function and resolve to their arguments, or ReturnValue<...> which does the same for return value, etc. as well as other cool things like Exclude and so on. I don't think this plugin will ever quite reach TypeScript's power, but I recently came across a situation where I was typing a pcall-like function, and would've liked to express that it takes the same extra arguments that the function itself takes.

Would also probably require a new annotation for declaring the entirety of a vararg (as a TyMultipleResults ) rather than the type of each element of the vararg.

Quick demonstration:

-- `varargs` annotation below. as opposed to `vararg` which specifies the type of each vararg,
-- `varargs` specifies the type of all of the entire varargs

--- @generic F: function
--- @param func F @function to spawn in a new thread
--- @varargs Parameters<F> @parameters to call the function with
--- @return ReturnValues<F>
function thread.spawn(func, ...) end

thread.spawn(function(a, b, c)
    -- a, b, c are all inferred as number due to the below parameters
end, 1, 2, 3)

thread.spawn(some_func, 1, 2,3) -- either some_func is required to take (number, number, number), or the arguments after some_func 

Would also make pcall more accurate

[Xseba360]

Something like Partial<Type> , Omit<Type, Keys> and Exclude<UnionType, ExcludedMembers> would be very handy

https://www.typescriptlang.org/docs/handbook/utility-types.html