Flow version: 0.171.0

Expected behavior

I'd expect both of these snippets of code to generate the same error, but only the normal generic errors, the $Call generated one does not:

type ToFunction<Parameter> = (x: Parameter) => string;
declare var expectString : ToFunction<string>;

expectString(10); // Correctly gives me an error
 
type _ToFunctionFromCall = <Parameter> (Parameter) => (x: Parameter) => string;
type ToFunctionFromCall<Parameter> = $Call<_ToFunctionFromCall, string>;

declare var expectStringFromCall : ToFunctionFromCall<string>;

// Does not give me an error, instead changes type of `expectStringFromCall`
// to (string | number) => string;
expectStringFromCall(10); 

I need the call version because I am passing it to $ObjMap. Currently, the $ObjMap appears like it's working, as hovering over the resultant types shows me what I expect to see ({ a: number => string, b: boolean => string, etc. }). Yet the second I try to use any of them, it just changes their parameter types to accept anything I pass to them.

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