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// @strict: true
const fn1 = <Params>(
params: Pick<Params, Exclude<keyof Params, never>>,
): Params => params;
function fn2<T>(x: Exclude<T, never>) {
var y: T = x;
x = y;
}
const fn3 = <Params>(
params: Pick<Params, Extract<keyof Params, keyof Params>>,
): Params => params;
function fn4<T>(x: Extract<T, T>) {
var y: T = x;
x = y;
}
declare var x: Extract<number | string, any>; // Should be `numebr | string` and not `any`
type ExtractWithDefault<T, U, D = never> = T extends U ? T : D;
type ExcludeWithDefault<T, U, D = never> = T extends U ? D : T;
const fn5 = <Params>(
params: Pick<Params, ExcludeWithDefault<keyof Params, never>>,
): Params => params;
function fn6<T>(x: ExcludeWithDefault<T, never>) {
var y: T = x;
x = y;
}
const fn7 = <Params>(
params: Pick<Params, ExtractWithDefault<keyof Params, keyof Params>>,
): Params => params;
function fn8<T>(x: ExtractWithDefault<T, T>) {
var y: T = x;
x = y;
}
type TemplatedConditional<TCheck, TExtends, TTrue, TFalse> = TCheck extends TExtends ? TTrue : TFalse;
const fn9 = <Params>(
params: Pick<Params, TemplatedConditional<keyof Params, never, never, keyof Params>>,
): Params => params;
function fn10<T>(x: TemplatedConditional<T, never, never, T>) {
var y: T = x;
x = y;
}
const fn11 = <Params>(
params: Pick<Params, TemplatedConditional<keyof Params, keyof Params, keyof Params, never>>,
): Params => params;
function fn12<T>(x: TemplatedConditional<T, T, T, never>) {
var y: T = x;
x = y;
}
declare var z: any;
const zee = z!!!; // since x is `any`, `x extends null | undefined` should be both true and false - and thus yield `any`
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