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

#### stdlib_assert_napi_value_is_type( env, value, type, \message, \err )

Asserts that a Node-API value is a specified Node-API data type.

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

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

// ...

napi_value err;
napi_status status = stdlib_assert_napi_value_is_type( env, value, napi_number, "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.
- type: [in] napi_valuetype Node-API data type.
- message: [in] char* error message.
- err: [out] napi_value* pointer for storing a JavaScript error.

`c
napi_status stdlib_assert_napi_value_is_type( const napi_env env, const napi_value value, const napi_valuetype type, const char message, napi_value err );
`

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