Class Decoder

Readonlysource

attachContext

• attachContext(context?: unknown): void

  Attach context to the decoder.

  The context object can be used to pass some "global" parameters down to custom decoders.

  Parameters

  • Optionalcontext: unknown

  Returns void

bitVecFixLen

• bitVecFixLen(bitLength: number): BitVec

  Decode a fixed-length sequence of bits of given length.

  Parameters

  • bitLength: number

  Returns BitVec

bitVecVarLen

• bitVecVarLen(): BitVec

  Decode a variable-length sequence of bits.

  Returns BitVec

bool

• bool(): boolean

  Decode a boolean discriminator.

  NOTE: this method will throw an exception in case the encoded byte is neither 0 nor 1.

  Returns boolean

bytes

• bytes<N extends number>(len: N): Bytes<N>

  Decode a fixed-length sequence of bytes.

  Type Parameters

  • N extends number

  Parameters

  • len: N

  Returns Bytes<N>

bytesBlob

• bytesBlob(): BytesBlob

  Decode a variable-length sequence of bytes.

  Returns BytesBlob

bytesRead

• bytesRead(): number

  Return the number of bytes read from the source (i.e. current offset within the source).

  Returns number

clone

• clone(): Decoder

  Return a copy of this decoder.

  The copy will maintain it's own offset within the source.

  Returns Decoder

finish

• finish(): void

  Finish decoding source object and make sure there is no data left.

  This method can be called when the entire object that was meant to be stored in the source is now fully decoded and we want to ensure that there is no extra bytes contained in the source.

  Returns void

getContext

• getContext(): unknown

  Get the decoding context object.

  Returns unknown

i16

• i16(): number

  Decode two bytes as a signed number.

  Returns number

i24

• i24(): number

  Decode three bytes as a signed number.

  Returns number

i32

• i32(): number

  Decode 4 bytes as a signed number.

  Returns number

i64

• i64(): bigint

  Decode 8 bytes as a signed number.

  Returns bigint

i8

• i8(): number

  Decode single byte as a signed number.

  Returns number

object

• object<T>(decode: Decode<T>): T

  Decode a composite object.

  Type Parameters

  • T

  Parameters

  • decode: Decode<T>

  Returns T

optional

• optional<T>(decode: Decode<T>): T | null

  Decode a possibly optional value.

  Type Parameters

  • T

  Parameters

  • decode: Decode<T>

  Returns T | null

remainingBytes

• remainingBytes(): BytesBlob

  Return all remaining bytes as BytesBlob and move offset to the end.

  Returns BytesBlob

resetTo

• resetTo(newOffset: number): void

  Move the decoding cursor to given offset.

  Note the offset can actually be smaller than the current offset (i.e. one can go back).

  Parameters

  • newOffset: number

  Returns void

sequenceFixLen

• sequenceFixLen<T>(decode: Decode<T>, len: number): T[]

  Decode a known-length sequence of elements.

  Type Parameters

  • T

  Parameters

  • decode: Decode<T>
  • len: number

  Returns T[]

sequenceVarLen

• sequenceVarLen<T>(decode: Decode<T>): T[]

  Decode a variable-length sequence of elements.

  Type Parameters

  • T

  Parameters

  • decode: Decode<T>

  Returns T[]

skip

• skip(bytes: number): void

  Skip given number of bytes for decoding.

  Parameters

  • bytes: number

  Returns void

u16

• u16(): U16

  Decode two bytes as an unsigned number.

  Returns U16

u24

• u24(): number

  Decode three bytes as an unsigned number.

  Returns number

u32

• u32(): U32

  Decode 4 bytes as an unsigned number.

  Returns U32

u64

• u64(): U64

  Decode 8 bytes as a unsigned number.

  Returns U64

u8

• u8(): U8

  Decode single byte as an unsigned number.

  Returns U8

varU32

• varU32(): U32

  Decode a variable-length encoding of natural numbers (up to 2**32).

  NOTE: this method will panic in case a larger number is found in the source.

  Returns U32

varU64

• varU64(): U64

  Decode a variable-length encoding of natural numbers (up to 2**64).

  Returns U64

StaticdecodeObject

• decodeObject<T>(
      decode: Decode<T>,
      source: Uint8Array<ArrayBufferLike> | BytesBlob,
      context?: unknown,
  ): T

  Decode a single object from all of the source bytes.

  NOTE that if you need to decode multiple objects, it might be better to create a [Decoder] instance intstead of slicing the data.

  Type Parameters

  • T

  Parameters

  • decode: Decode<T>
  • source: Uint8Array<ArrayBufferLike> | BytesBlob
  • Optionalcontext: unknown

  Returns T

StaticdecodeSequence

• decodeSequence<T>(
      decode: Decode<T>,
      source: Uint8Array<ArrayBufferLike> | BytesBlob,
      context?: unknown,
  ): T[]

  Decode a sequence of objects from all of the source bytes.

  Type Parameters

  • T

  Parameters

  • decode: Decode<T>
  • source: Uint8Array<ArrayBufferLike> | BytesBlob
  • Optionalcontext: unknown

  Returns T[]

StaticfromBlob

• fromBlob(source: Uint8Array, context?: unknown): Decoder

  Create a new [Decoder] instance given a raw array of bytes as a source.

  Parameters

  • source: Uint8Array
  • Optionalcontext: unknown

  Returns Decoder

StaticfromBytesBlob

• fromBytesBlob(source: BytesBlob, offset?: number): Decoder

  Create a new [Decoder] instance from given bytes blob and starting offset.

  Parameters

  • source: BytesBlob
  • Optionaloffset: number

  Returns Decoder