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BigInt

Class Napi::Bigint inherits from class Napi::Value.

A JavaScript BigInt value.

Methods

New

static Napi::BigInt Napi::BigInt::New(Napi::Env env, int64_t value);
static Napi::BigInt Napi::BigInt::New(Napi::Env env, uint64_t value);
  • [in] env: The environment in which to construct the Napi::BigInt object.
  • [in] value: The value the JavaScript BigInt will contain

These APIs convert the C int64_t and uint64_t types to the JavaScript BigInt type.

static Napi::BigInt Napi::BigInt::New(Napi::Env env,
                  int sign_bit,
                  size_t word_count,
                  const uint64_t* words);
  • [in] env: The environment in which to construct the Napi::BigInt object.
  • [in] sign_bit: Determines if the resulting BigInt will be positive or negative.
  • [in] word_count: The length of the words array.
  • [in] words: An array of uint64_t little-endian 64-bit words.

This API converts an array of unsigned 64-bit words into a single BigInt value.

The resulting BigInt is calculated as: (–1)sign_bit (words[0] × (264)0 + words[1] × (264)1 + …)

Returns a new JavaScript BigInt.

Constructor

Napi::BigInt();

Returns a new empty JavaScript Napi::BigInt.

Int64Value

int64_t Napi::BigInt::Int64Value(bool* lossless) const;
  • [out] lossless: Indicates whether the BigInt value was converted losslessly.

Returns the C int64_t primitive equivalent of the given JavaScript BigInt. If needed it will truncate the value, setting lossless to false.

Uint64Value

uint64_t Napi::BigInt::Uint64Value(bool* lossless) const;
  • [out] lossless: Indicates whether the BigInt value was converted losslessly.

Returns the C uint64_t primitive equivalent of the given JavaScript BigInt. If needed it will truncate the value, setting lossless to false.

WordCount

size_t Napi::BigInt::WordCount() const;

Returns the number of words needed to store this BigInt value.

ToWords

void Napi::BigInt::ToWords(int* sign_bit, size_t* word_count, uint64_t* words);
  • [out] sign_bit: Integer representing if the JavaScript BigInt is positive or negative.
  • [in/out] word_count: Must be initialized to the length of the words array. Upon return, it will be set to the actual number of words that would be needed to store this BigInt.
  • [out] words: Pointer to a pre-allocated 64-bit word array.

Returns a single BigInt value into a sign bit, 64-bit little-endian array, and the number of elements in the array.