transformEncoder

Call Signature

transformEncoder<TOldFrom, TNewFrom, TSize>(encoder, unmap): FixedSizeEncoder<TNewFrom, TSize>

Transforms an encoder by mapping its input values.

This function takes an existing Encoder<A> and returns an Encoder<B>, allowing values of type B to be converted into values of type A before encoding. The transformation is applied via the unmap function.

This is useful for handling type conversions, applying default values, or structuring data before encoding.

For more details, see transformCodec.

Type Parameters

Type Parameter	Description
`TOldFrom`	The original type expected by the encoder.
`TNewFrom`	The new type that will be transformed before encoding.
`TSize` extends `number`	-

Parameters

Parameter	Type	Description
`encoder`	`FixedSizeEncoder`<`TOldFrom`, `TSize`>	The encoder to transform.
`unmap`	(`value`) => `TOldFrom`	A function that converts values of `TNewFrom` into `TOldFrom` before encoding.

Returns

FixedSizeEncoder<TNewFrom, TSize>

A new encoder that accepts TNewFrom values and transforms them before encoding.

Example

Encoding a string by counting its characters and storing the length as a u32.

const encoder = transformEncoder(getU32Encoder(), (value: string) => value.length);
encoder.encode("hello"); // 0x05000000 (stores length 5)

See

Call Signature

transformEncoder<TOldFrom, TNewFrom>(encoder, unmap): VariableSizeEncoder<TNewFrom>

Transforms an encoder by mapping its input values.

This is useful for handling type conversions, applying default values, or structuring data before encoding.

For more details, see transformCodec.

Type Parameters

Type Parameter	Description
`TOldFrom`	The original type expected by the encoder.
`TNewFrom`	The new type that will be transformed before encoding.

Parameters

Parameter	Type	Description
`encoder`	`VariableSizeEncoder`<`TOldFrom`>	The encoder to transform.
`unmap`	(`value`) => `TOldFrom`	A function that converts values of `TNewFrom` into `TOldFrom` before encoding.

Returns

VariableSizeEncoder<TNewFrom>

A new encoder that accepts TNewFrom values and transforms them before encoding.

Example

Encoding a string by counting its characters and storing the length as a u32.

const encoder = transformEncoder(getU32Encoder(), (value: string) => value.length);
encoder.encode("hello"); // 0x05000000 (stores length 5)

See

Call Signature

transformEncoder<TOldFrom, TNewFrom>(encoder, unmap): Encoder<TNewFrom>

Transforms an encoder by mapping its input values.

This is useful for handling type conversions, applying default values, or structuring data before encoding.

For more details, see transformCodec.

Type Parameters

Type Parameter	Description
`TOldFrom`	The original type expected by the encoder.
`TNewFrom`	The new type that will be transformed before encoding.

Parameters

Parameter	Type	Description
`encoder`	`Encoder`<`TOldFrom`>	The encoder to transform.
`unmap`	(`value`) => `TOldFrom`	A function that converts values of `TNewFrom` into `TOldFrom` before encoding.

Returns

Encoder<TNewFrom>

A new encoder that accepts TNewFrom values and transforms them before encoding.

Example

Encoding a string by counting its characters and storing the length as a u32.

const encoder = transformEncoder(getU32Encoder(), (value: string) => value.length);
encoder.encode("hello"); // 0x05000000 (stores length 5)

transformEncoder

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