getPatternMatchDecoder

Call Signature

function getPatternMatchDecoder<TTo, TSize>(
    patterns,
): FixedSizeDecoder<TTo, TSize>;

Returns a decoder that selects which variant decoder to use based on pattern matching.

This decoder evaluates the byte array against a series of predicate functions in order, and uses the first matching decoder to decode the value.

Type Parameters

Type Parameter	Description
`TTo`	The type of the value to decode.
`TSize` extends `number`	-

Parameters

Parameter	Type	Description
`patterns`	[(`value`) => `boolean`, `FixedSizeDecoder`<`TTo`, `TSize`>][]	An array of `[predicate, decoder]` pairs. Predicates are tested in order and the first matching decoder is used to decode the byte array.

Returns

FixedSizeDecoder<TTo, TSize>

A decoder that selects the appropriate variant based on the matched byte pattern.

Throws

Throws a SOLANA_ERROR__CODECS__INVALID_PATTERN_MATCH_BYTES error if the byte array does not match any of the specified patterns.

Example

Decoding values using pattern matching on bytes.

const decoder = getPatternMatchDecoder([
  [(bytes) => bytes.length === 1, getU8Decoder()],
  [(bytes) => bytes.length === 2, getU16Decoder()],
  [(bytes) => bytes.length <= 4, getU32Decoder()]
]);
 
decoder.decode(new Uint8Array([0x2a])); // 42 (decoded as u8)
decoder.decode(new Uint8Array([0xe8, 0x03])) // 1000 (decoded as u16)
decoder.decode(new Uint8Array([0xa0, 0x86, 0x01, 0x00])) // 100_000 (decoded as u32)
decoder.decode(new Uint8Array([0xa0, 0x86, 0x01, 0x00, 0x00]))
// Throws an error because the bytes do not match any pattern

See

Call Signature

function getPatternMatchDecoder<TTo>(patterns): FixedSizeDecoder<TTo>;

Returns a decoder that selects which variant decoder to use based on pattern matching.

This decoder evaluates the byte array against a series of predicate functions in order, and uses the first matching decoder to decode the value.

Type Parameters

Type Parameter	Description
`TTo`	The type of the value to decode.

Parameters

Parameter	Type	Description
`patterns`	[(`value`) => `boolean`, `FixedSizeDecoder`<`TTo`>][]	An array of `[predicate, decoder]` pairs. Predicates are tested in order and the first matching decoder is used to decode the byte array.

Returns

FixedSizeDecoder<TTo>

A decoder that selects the appropriate variant based on the matched byte pattern.

Throws

Throws a SOLANA_ERROR__CODECS__INVALID_PATTERN_MATCH_BYTES error if the byte array does not match any of the specified patterns.

Example

Decoding values using pattern matching on bytes.

const decoder = getPatternMatchDecoder([
  [(bytes) => bytes.length === 1, getU8Decoder()],
  [(bytes) => bytes.length === 2, getU16Decoder()],
  [(bytes) => bytes.length <= 4, getU32Decoder()]
]);
 
decoder.decode(new Uint8Array([0x2a])); // 42 (decoded as u8)
decoder.decode(new Uint8Array([0xe8, 0x03])) // 1000 (decoded as u16)
decoder.decode(new Uint8Array([0xa0, 0x86, 0x01, 0x00])) // 100_000 (decoded as u32)
decoder.decode(new Uint8Array([0xa0, 0x86, 0x01, 0x00, 0x00]))
// Throws an error because the bytes do not match any pattern

See

Call Signature

function getPatternMatchDecoder<TTo>(
    patterns,
): VariableSizeDecoder<TTo>;

Returns a decoder that selects which variant decoder to use based on pattern matching.

This decoder evaluates the byte array against a series of predicate functions in order, and uses the first matching decoder to decode the value.

Type Parameters

Type Parameter	Description
`TTo`	The type of the value to decode.

Parameters

Parameter	Type	Description
`patterns`	[(`value`) => `boolean`, `VariableSizeDecoder`<`TTo`>][]	An array of `[predicate, decoder]` pairs. Predicates are tested in order and the first matching decoder is used to decode the byte array.

Returns

VariableSizeDecoder<TTo>

A decoder that selects the appropriate variant based on the matched byte pattern.

Throws

Throws a SOLANA_ERROR__CODECS__INVALID_PATTERN_MATCH_BYTES error if the byte array does not match any of the specified patterns.

Example

Decoding values using pattern matching on bytes.

const decoder = getPatternMatchDecoder([
  [(bytes) => bytes.length === 1, getU8Decoder()],
  [(bytes) => bytes.length === 2, getU16Decoder()],
  [(bytes) => bytes.length <= 4, getU32Decoder()]
]);
 
decoder.decode(new Uint8Array([0x2a])); // 42 (decoded as u8)
decoder.decode(new Uint8Array([0xe8, 0x03])) // 1000 (decoded as u16)
decoder.decode(new Uint8Array([0xa0, 0x86, 0x01, 0x00])) // 100_000 (decoded as u32)
decoder.decode(new Uint8Array([0xa0, 0x86, 0x01, 0x00, 0x00]))
// Throws an error because the bytes do not match any pattern

See

Call Signature

function getPatternMatchDecoder<TTo>(patterns): Decoder<TTo>;

Returns a decoder that selects which variant decoder to use based on pattern matching.

This decoder evaluates the byte array against a series of predicate functions in order, and uses the first matching decoder to decode the value.

Type Parameters

Type Parameter	Description
`TTo`	The type of the value to decode.

Parameters

Parameter	Type	Description
`patterns`	[(`value`) => `boolean`, `Decoder`<`TTo`>][]	An array of `[predicate, decoder]` pairs. Predicates are tested in order and the first matching decoder is used to decode the byte array.

const decoder = getPatternMatchDecoder([
  [(bytes) => bytes.length === 1, getU8Decoder()],
  [(bytes) => bytes.length === 2, getU16Decoder()],
  [(bytes) => bytes.length <= 4, getU32Decoder()]
]);
 
decoder.decode(new Uint8Array([0x2a])); // 42 (decoded as u8)
decoder.decode(new Uint8Array([0xe8, 0x03])) // 1000 (decoded as u16)
decoder.decode(new Uint8Array([0xa0, 0x86, 0x01, 0x00])) // 100_000 (decoded as u32)
decoder.decode(new Uint8Array([0xa0, 0x86, 0x01, 0x00, 0x00]))
// Throws an error because the bytes do not match any pattern

getPatternMatchDecoder

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