| 1 | import { deepEqual } from "../internal"
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| 2 |
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| 3 | export interface IEqualsComparer<T> {
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| 4 | (a: T, b: T): boolean
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| 5 | }
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| 6 |
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| 7 | function identityComparer(a: any, b: any): boolean {
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| 8 | return a === b
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| 9 | }
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| 10 |
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| 11 | function structuralComparer(a: any, b: any): boolean {
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| 12 | return deepEqual(a, b)
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| 13 | }
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| 14 |
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| 15 | function shallowComparer(a: any, b: any): boolean {
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| 16 | return deepEqual(a, b, 1)
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| 17 | }
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| 18 |
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| 19 | function defaultComparer(a: any, b: any): boolean {
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| 20 | if (Object.is) return Object.is(a, b)
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| 21 |
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| 22 | return a === b
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| 23 | ? a !== 0 || 1 / a === 1 / b
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| 24 | : a !== a && b !== b
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| 25 | }
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| 26 |
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| 27 | export const comparer = {
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| 28 | identity: identityComparer,
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| 29 | structural: structuralComparer,
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| 30 | default: defaultComparer,
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| 31 | shallow: shallowComparer
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| 32 | }
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