assertion-error

AssertionError and AssertionResult classes.

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What is AssertionError?

Assertion Error is a module that contains two classes: AssertionError, which
is an instance of an Error, and AssertionResult which is not an instance of
Error.

These can be useful for returning from a function - if the function "succeeds"
return an AssertionResult and if the function fails return (or throw) an
AssertionError.

Both AssertionError and AssertionResult implement the Result interface:

``typescript
interface Result {
name: "AssertionError" | "AssertionResult";
ok: boolean;
toJSON(...args: unknown[]): Record;
}
`

So if a function returns AssertionResult | AssertionError it is easy to check
_which_ one is returned by checking either .name or .ok, or check
instanceof Error.

Installation

$3

assertion-error is available on npm.

`
$ npm install --save assertion-error
`

$3

assertion_error is available on
Deno.land

`typescript
import {
AssertionError,
AssertionResult,
} from "https://deno.land/x/assertion_error@2.0.0/mod.ts";
``