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=== tests/cases/compiler/typePredicateFreshLiteralWidening.ts ===
type Narrowable = string | number | bigint | boolean;
>Narrowable : string | number | bigint | boolean
type Narrow<A> = (A extends Narrowable ? A : never) | ({
>Narrow : Narrow<A>
[K in keyof A]: Narrow<A[K]>;
});
const satisfies =
>satisfies : <TWide>() => <TNarrow extends TWide>(narrow: Narrow<TNarrow>) => Narrow<TNarrow>
<TWide,>() =>
><TWide,>() => <TNarrow extends TWide>(narrow: Narrow<TNarrow>) => narrow : <TWide>() => <TNarrow extends TWide>(narrow: Narrow<TNarrow>) => Narrow<TNarrow>
<TNarrow extends TWide>(narrow: Narrow<TNarrow>) =>
><TNarrow extends TWide>(narrow: Narrow<TNarrow>) => narrow : <TNarrow extends TWide>(narrow: Narrow<TNarrow>) => Narrow<TNarrow>
>narrow : Narrow<TNarrow>
narrow;
>narrow : Narrow<TNarrow>
/* ========================================================================== */
const isNotNull = <T,>(value: T | null): value is T => value !== null;
>isNotNull : <T>(value: T | null) => value is T
><T,>(value: T | null): value is T => value !== null : <T>(value: T | null) => value is T
>value : T | null
>null : null
>value !== null : boolean
>value : T | null
>null : null
type Item = { value: string | null };
>Item : { value: string | null; }
>value : string | null
>null : null
const item1 = satisfies<Item>()({ value: "1" });
>item1 : { value: "1"; }
>satisfies<Item>()({ value: "1" }) : { value: "1"; }
>satisfies<Item>() : <TNarrow extends Item>(narrow: Narrow<TNarrow>) => Narrow<TNarrow>
>satisfies : <TWide>() => <TNarrow extends TWide>(narrow: Narrow<TNarrow>) => Narrow<TNarrow>
>{ value: "1" } : { value: "1"; }
>value : "1"
>"1" : "1"
const item2 = satisfies<Item>()({ value: "2" });
>item2 : { value: "2"; }
>satisfies<Item>()({ value: "2" }) : { value: "2"; }
>satisfies<Item>() : <TNarrow extends Item>(narrow: Narrow<TNarrow>) => Narrow<TNarrow>
>satisfies : <TWide>() => <TNarrow extends TWide>(narrow: Narrow<TNarrow>) => Narrow<TNarrow>
>{ value: "2" } : { value: "2"; }
>value : "2"
>"2" : "2"
const item3 = satisfies<Item>()({ value: null });
>item3 : { value: null; }
>satisfies<Item>()({ value: null }) : { value: null; }
>satisfies<Item>() : <TNarrow extends Item>(narrow: Narrow<TNarrow>) => Narrow<TNarrow>
>satisfies : <TWide>() => <TNarrow extends TWide>(narrow: Narrow<TNarrow>) => Narrow<TNarrow>
>{ value: null } : { value: null; }
>value : null
>null : null
const values2: Array<"1" | "2" | null> = ["1", "2", null];
>values2 : ("1" | "2" | null)[]
>null : null
>["1", "2", null] : ("1" | "2" | null)[]
>"1" : "1"
>"2" : "2"
>null : null
const filteredValues2 = values2.filter(isNotNull);
>filteredValues2 : ("1" | "2")[]
>values2.filter(isNotNull) : ("1" | "2")[]
>values2.filter : { <S extends "1" | "2" | null>(predicate: (value: "1" | "2" | null, index: number, array: ("1" | "2" | null)[]) => value is S, thisArg?: any): S[]; (predicate: (value: "1" | "2" | null, index: number, array: ("1" | "2" | null)[]) => unknown, thisArg?: any): ("1" | "2" | null)[]; }
>values2 : ("1" | "2" | null)[]
>filter : { <S extends "1" | "2" | null>(predicate: (value: "1" | "2" | null, index: number, array: ("1" | "2" | null)[]) => value is S, thisArg?: any): S[]; (predicate: (value: "1" | "2" | null, index: number, array: ("1" | "2" | null)[]) => unknown, thisArg?: any): ("1" | "2" | null)[]; }
>isNotNull : <T>(value: T | null) => value is T
const values1 = [item1, item2, item3].map(item => item.value);
>values1 : ("1" | "2" | null)[]
>[item1, item2, item3].map(item => item.value) : ("1" | "2" | null)[]
>[item1, item2, item3].map : <U>(callbackfn: (value: { value: "1"; } | { value: "2"; } | { value: null; }, index: number, array: ({ value: "1"; } | { value: "2"; } | { value: null; })[]) => U, thisArg?: any) => U[]
>[item1, item2, item3] : ({ value: "1"; } | { value: "2"; } | { value: null; })[]
>item1 : { value: "1"; }
>item2 : { value: "2"; }
>item3 : { value: null; }
>map : <U>(callbackfn: (value: { value: "1"; } | { value: "2"; } | { value: null; }, index: number, array: ({ value: "1"; } | { value: "2"; } | { value: null; })[]) => U, thisArg?: any) => U[]
>item => item.value : (item: { value: "1"; } | { value: "2"; } | { value: null; }) => "1" | "2" | null
>item : { value: "1"; } | { value: "2"; } | { value: null; }
>item.value : "1" | "2" | null
>item : { value: "1"; } | { value: "2"; } | { value: null; }
>value : "1" | "2" | null
const filteredValues1 = values1.filter(isNotNull);
>filteredValues1 : ("1" | "2")[]
>values1.filter(isNotNull) : ("1" | "2")[]
>values1.filter : { <S extends "1" | "2" | null>(predicate: (value: "1" | "2" | null, index: number, array: ("1" | "2" | null)[]) => value is S, thisArg?: any): S[]; (predicate: (value: "1" | "2" | null, index: number, array: ("1" | "2" | null)[]) => unknown, thisArg?: any): ("1" | "2" | null)[]; }
>values1 : ("1" | "2" | null)[]
>filter : { <S extends "1" | "2" | null>(predicate: (value: "1" | "2" | null, index: number, array: ("1" | "2" | null)[]) => value is S, thisArg?: any): S[]; (predicate: (value: "1" | "2" | null, index: number, array: ("1" | "2" | null)[]) => unknown, thisArg?: any): ("1" | "2" | null)[]; }
>isNotNull : <T>(value: T | null) => value is T
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