assert

The assert module provides some simple assertion methods for type checks, truthyness tests and guards invalid code paths. When importing the module as default module, it is the assert function itself.

It can be imported as assert from 'laxar';

Contents

Module Members

• assert()

Types

• Assertion

  • Assertion.isNotNull()
  • Assertion.hasType()
  • Assertion.hasProperty()

• assert

  • assert.codeIsUnreachable()
  • assert.state()

Module Members

assert( subject, optionalDetails )

Creates and returns a new Assertion instance for the given subject.

Note: this function is no member of the module, but the module itself. Thus when using assert via laxar, assert is will be no simple object, but this function having the other functions as properties.

Example:

import { assert } from 'laxar';
assert( assert ).hasType( Function );
assert.state( typeof assert.codeIsUnreachable === 'function' );

Parameters

Returns

Types

Assertion

Assertion.isNotNull( optionalDetails )

Throws an error if the subject is null or undefined.

Parameters

Returns

Assertion.hasType( type, optionalDetails )

Throws an error if the subject is not of the given type. No error is thrown for null or undefined.

Parameters

Returns

Assertion.hasProperty( property, optionalDetails )

Throws an error if the subject is no object or the given property is not defined on it.

Parameters

Returns

assert

assert.codeIsUnreachable( optionalDetails )

Marks a code path as erroneous by throwing an error when reached.

Parameters

assert.state( expression, optionalDetails )

Throws an error if the given expression is falsy.

Parameters