npm package: @stdlib/assert-napi-has-property
Description: Assert that a Node-API value has a specified property.
Author: The Stdlib Authors
Latest version: 0.0.3

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<details>
  <summary>
    About stdlib...
  </summary>
  <p>We believe in a future in which the web is a preferred environment for numerical computation. To help realize this future, we've built stdlib. stdlib is a standard library, with an emphasis on numerical and scientific computation, written in JavaScript (and C) for execution in browsers and in Node.js.</p>
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# Assert Property

[![NPM version][npm-image]][npm-url] [![Build Status][test-image]][test-url] [![Coverage Status][coverage-image]][coverage-url] <!-- [![dependencies][dependencies-image]][dependencies-url] -->

> Assert that a Node-API value has a specified property.

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<section class="intro">

</section>

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<!-- Package usage documentation. -->

<section class="installation">

## Installation

```bash
npm install @stdlib/assert-napi-has-property
```

</section>

<section class="usage">

## Usage

```javascript
var headerDir = require( '@stdlib/assert-napi-has-property' );
```

#### headerDir

Absolute file path for the directory containing header files for C APIs.

```javascript
var dir = headerDir;
// returns <string>
```

</section>

<!-- /.usage -->

<!-- Package usage notes. Make sure to keep an empty line after the `section` element and another before the `/section` close. -->

<section class="notes">

</section>

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<!-- Package usage examples. -->

<section class="examples">

## Examples

```javascript
var headerDir = require( '@stdlib/assert-napi-has-property' );

console.log( headerDir );
// => <string>
```

</section>

<!-- /.examples -->

<!-- C interface documentation. -->

* * *

<section class="c">

## C APIs

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<section class="intro">

</section>

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<!-- C usage documentation. -->

<section class="usage">

### Usage

```c
#include "stdlib/assert/napi/has_property.h"
```

#### stdlib_assert_napi_value_has_property( env, value, \*property, \*message, \*err )

Asserts that a Node-API value has a specified property.

```c
#include "stdlib/assert/napi/has_property.h"
#include <node_api.h>

static napi_value addon( napi_env env, napi_callback_info info ) {
    napi_value value;

    // ...

    napi_value err;
    napi_status status = stdlib_assert_napi_value_has_property( env, value, "foo", "Missing property.", &err );
    assert( status == napi_ok );
    if ( err != NULL ) {
        assert( napi_throw( env, err ) == napi_ok );
        return NULL;
    }

    // ...
}
```

The function accepts the following arguments:

-   **env**: `[in] napi_env` environment under which the function is invoked.
-   **value**: `[in] napi_value` Node-API value.
-   **property**: `[in] char*` property name.
-   **message**: `[in] char*` error message.
-   **err**: `[out] napi_value*` pointer for storing a JavaScript error.

```c
napi_status stdlib_assert_napi_value_has_property( const napi_env env, const napi_value value, const char *property, const char *message, napi_value *err );
```

The function returns a `napi_status` status code indicating success or failure (returns `napi_ok` if success).

</section>

<!-- /.usage -->

<!-- C API usage notes. Make sure to keep an empty line after the `section` element and another before the `/section` close. -->

<section class="notes">

### Notes

-   If the value does not have the specified property, the function sets `err` with a JavaScript error; otherwise, `err` is set to `NULL`.

</section>

<!-- /.notes -->

<!-- C API usage examples. -->

<section class="examples">

</section>

<!-- /.examples -->

</section>

<!-- /.c -->

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</section>

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<section class="related">

</section>

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<section class="main-repo" >

* * *

## Notice

This package is part of [stdlib][stdlib], a standard library for JavaScript and Node.js, with an emphasis on numerical and scientific computing. The library provides a collection of robust, high performance libraries for mathematics, statistics, streams, utilities, and more.

For more information on the project, filing bug reports and feature requests, and guidance on how to develop [stdlib][stdlib], see the main project [repository][stdlib].

#### Community

[![Chat][chat-image]][chat-url]

---

## License

See [LICENSE][stdlib-license].


## Copyright

Copyright &copy; 2016-2026. The Stdlib [Authors][stdlib-authors].

</section>

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