getNullableDecoder

Call Signature

getNullableDecoder<TTo, TSize>(item, config): FixedSizeDecoder<null | TTo, TSize>

Returns a decoder for optional values, allowing null values to be recognized.

This decoder deserializes an optional value using a configurable approach:

By default, a u8 prefix is used (0 = null, 1 = present). This can be customized or disabled.
If noneValue: 'zeroes' is set, null values are identified by zeroes.
If noneValue is a byte array, null values match the provided constant.

Type Parameters

Type Parameter	Description
`TTo`	The type of the main value being decoded.
`TSize` extends `number`	-

Parameters

Parameter	Type	Description
`item`	`FixedSizeDecoder`<`TTo`, `TSize`>	The decoder for the value that may be present.
`config`	`NullableCodecConfig`<`NumberDecoder`> & `object`	Configuration options for decoding optional values.

Returns

FixedSizeDecoder<null | TTo, TSize>

A FixedSizeDecoder or VariableSizeDecoder for decoding nullable values.

Example

Decoding an optional number.

const decoder = getNullableDecoder(getU32Decoder());
 
decoder.decode(new Uint8Array([0x00])); // null
decoder.decode(new Uint8Array([0x01, 0x2a, 0x00, 0x00, 0x00])); // 42

See

getNullableCodec

Call Signature

getNullableDecoder<TTo>(item, config): FixedSizeDecoder<null | TTo>

Returns a decoder for optional values, allowing null values to be recognized.

This decoder deserializes an optional value using a configurable approach:

By default, a u8 prefix is used (0 = null, 1 = present). This can be customized or disabled.
If noneValue: 'zeroes' is set, null values are identified by zeroes.
If noneValue is a byte array, null values match the provided constant.

For more details, see getNullableCodec.

Type Parameters

Type Parameter	Description
`TTo`	The type of the main value being decoded.

Parameters

Parameter	Type	Description
`item`	`FixedSizeDecoder`<`TTo`>	The decoder for the value that may be present.
`config`	`NullableCodecConfig`<`FixedSizeNumberDecoder`> & `object`	Configuration options for decoding optional values.

Returns

FixedSizeDecoder<null | TTo>

A FixedSizeDecoder or VariableSizeDecoder for decoding nullable values.

Example

Decoding an optional number.

const decoder = getNullableDecoder(getU32Decoder());
 
decoder.decode(new Uint8Array([0x00])); // null
decoder.decode(new Uint8Array([0x01, 0x2a, 0x00, 0x00, 0x00])); // 42

See

getNullableCodec

Call Signature

getNullableDecoder<TTo>(item, config): VariableSizeDecoder<null | TTo>

Returns a decoder for optional values, allowing null values to be recognized.

This decoder deserializes an optional value using a configurable approach:

By default, a u8 prefix is used (0 = null, 1 = present). This can be customized or disabled.
If noneValue: 'zeroes' is set, null values are identified by zeroes.
If noneValue is a byte array, null values match the provided constant.

For more details, see getNullableCodec.

Type Parameters

Type Parameter	Description
`TTo`	The type of the main value being decoded.

Parameters

Parameter	Type	Description
`item`	`FixedSizeDecoder`<`TTo`>	The decoder for the value that may be present.
`config`	`NullableCodecConfig`<`NumberDecoder`> & `object`	Configuration options for decoding optional values.

Returns

VariableSizeDecoder<null | TTo>

A FixedSizeDecoder or VariableSizeDecoder for decoding nullable values.

Example

Decoding an optional number.

const decoder = getNullableDecoder(getU32Decoder());
 
decoder.decode(new Uint8Array([0x00])); // null
decoder.decode(new Uint8Array([0x01, 0x2a, 0x00, 0x00, 0x00])); // 42

See

getNullableCodec

Call Signature

getNullableDecoder<TTo>(item, config?): VariableSizeDecoder<null | TTo>

Returns a decoder for optional values, allowing null values to be recognized.

This decoder deserializes an optional value using a configurable approach:

By default, a u8 prefix is used (0 = null, 1 = present). This can be customized or disabled.
If noneValue: 'zeroes' is set, null values are identified by zeroes.
If noneValue is a byte array, null values match the provided constant.

For more details, see getNullableCodec.

Type Parameters

Type Parameter	Description
`TTo`	The type of the main value being decoded.

Parameters

Parameter	Type	Description
`item`	`Decoder`<`TTo`>	The decoder for the value that may be present.
`config?`	`NullableCodecConfig`<`NumberDecoder`> & `object`	Configuration options for decoding optional values.

Returns

VariableSizeDecoder<null | TTo>

A FixedSizeDecoder or VariableSizeDecoder for decoding nullable values.

Example

Decoding an optional number.

const decoder = getNullableDecoder(getU32Decoder());
 
decoder.decode(new Uint8Array([0x00])); // null
decoder.decode(new Uint8Array([0x01, 0x2a, 0x00, 0x00, 0x00])); // 42

See

getNullableCodec

getNullableDecoder

On this page