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// Copyright 2018-2023 the Deno authors. All rights reserved. MIT license.// This module is browser compatible.
/** * All internal non-test code, that is files that do not have `test` or `bench` in the name, must use the assertion functions within `_utils/asserts.ts` and not `testing/asserts.ts`. This is to create a separation of concerns between internal and testing assertions. */
export class DenoStdInternalError extends Error { constructor(message: string) { super(message); = "DenoStdInternalError"; }}
/** Make an assertion, if not `true`, then throw. */export function assert(expr: unknown, msg = ""): asserts expr { if (!expr) { throw new DenoStdInternalError(msg); }}
/** Use this to assert unreachable code. */export function unreachable(): never { throw new DenoStdInternalError("unreachable");}