@stdlib/napi-argv-uint32
v0.2.2
Published
Convert a Node-API value to an unsigned 32-bit integer.
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argv_uint32
Convert a Node-API value to an unsigned 32-bit integer.
Installation
npm install @stdlib/napi-argv-uint32
Usage
var headerDir = require( '@stdlib/napi-argv-uint32' );
headerDir
Absolute file path for the directory containing header files for C APIs.
var dir = headerDir;
// returns <string>
Examples
var headerDir = require( '@stdlib/napi-argv-uint32' );
console.log( headerDir );
// => <string>
C APIs
Usage
#include "stdlib/napi/argv_uint32.h"
stdlib_napi_argv_uint32( env, value, *out, *message, *err )
Converts a Node-API value to an unsigned 32-bit integer.
#include "stdlib/napi/argv_uint32.h"
#include <node_api.h>
#include <stdint.h>
static napi_value addon( napi_env env, napi_callback_info info ) {
napi_value value;
// ...
uint32_t out;
napi_value err;
napi_status status = stdlib_napi_argv_uint32( env, value, &out, "Must be a number.", &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. - out:
[out] uint32_t*
destination for storing output value. - message:
[in] char*
error message. - err:
[out] napi_value*
pointer for storing a JavaScript error. If not provided a number, the function setserr
with a JavaScript error; otherwise,err
is set toNULL
.
napi_status stdlib_napi_argv_uint32( const napi_env env, const napi_value value, uint32_t *out, const char *message, napi_value *err );
The function returns a napi_status
status code indicating success or failure (returns napi_ok
if success).
STDLIB_NAPI_ARGV_UINT32( env, name, argv, index )
Macro for converting an add-on callback argument to an unsigned 32-bit integer.
#include "stdlib/napi/argv_uint32.h"
#include "stdlib/napi/argv.h"
#include <node_api.h>
#include <stdint.h>
static uint32_t fcn( const uint32_t v ) {
return v;
}
// ...
static napi_value addon( napi_env env, napi_callback_info info ) {
// Retrieve add-on callback arguments:
STDLIB_NAPI_ARGV( env, info, argv, argc, 1 );
// Convert the first argument to a C type:
STDLIB_NAPI_ARGV_UINT32( env, value, argv, 0 );
// ...
uint32_t out = fcn( value );
}
The macro expects the following arguments:
- env: environment under which the callback is invoked.
- name: output variable name.
- argv: name of the variable containing add-on callback arguments.
- index: argument index.
Notice
This package is part of 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, see the main project repository.
Community
License
See LICENSE.
Copyright
Copyright © 2016-2024. The Stdlib Authors.