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std/_util/assert_type.ts

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// Copyright 2018-2022 the Deno authors. All rights reserved. MIT license.// Original author: @dsherret https://github.com/dsherret/conditional-type-checks
/** * Asserts at compile time that the provided type argument's type resolves to the expected boolean literal type. * @param _expectTrue - True if the passed in type argument resolved to true. */export function assertType<T extends true | false>(_expectTrue: T) {}
/** * Checks if type `T` exactly matches type `U`. */export type IsExact<T, U> = TupleMatches<AnyToBrand<T>, AnyToBrand<U>> extends true ? TupleMatches< DeepMakeRequiredForIsExact<T>, DeepMakeRequiredForIsExact<U> > extends true // catch optional properties ? true : false : false;
type DeepMakeRequiredForIsExact<T> = { [P in keyof T]-?: DeepMakeRequiredForIsExact<AnyToBrand<T[P]>>;};
/** * Checks if type `T` is the `any` type. */// https://stackoverflow.com/a/49928360/3406963export type IsAny<T> = 0 extends (1 & T) ? true : false;
type TupleMatches<T, U> = Matches<[T], [U]> extends true ? true : false;type Matches<T, U> = T extends U ? U extends T ? true : false : false;
type AnyToBrand<T> = IsAny<T> extends true ? { __conditionalTypeChecksAny__: undefined } : T;