Module abi

Ethereum ABI codec implementation.

This module provides the low-level ABI Encoder and Decoder structs, along with generic functions for their operation. These utilize an intermediate representation, referred to as tokens. For additional information about tokens, see the token module documentation.

You should not need this module in most cases, as the SolType and SolValue traits provide a higher-level and easier to use interface. If you’re sure you need the low-level functionality of this module, there are three main interfaces:

{encode,decode}

encode operates on a single token. It wrap this token in a single-element tuple, and passes it to the encoder. Similarly, decode decodes a single token from a blob by decoding a single-element tuple.

Use this interface when ABI-encoding a single token. This is suitable for encoding a type in isolation, or for encoding parameters for single-param functions.

{encode,decode}_params

encode_params operates on a sequence. If the sequence is a tuple, the tuple is inferred to be a set of Solidity function parameters, The corresponding decode_params reverses this operation, decoding a tuple from a blob.

This is used to encode the parameters for a Solidity function.

{encode,decode}_sequence

encode_sequence operates on a sequence of tokens. This sequence is inferred not to be function parameters.

This is the least useful one. Most users will not need it.

Re-exports

pub use token::Token;

pub use token::TokenSeq;

Modules

token

Ethereum ABI tokens.

Structs

Decoder

The Decoder wraps a byte slice with necessary info to progressively deserialize the bytes into a sequence of tokens.

Encoder

An ABI encoder.

Constants

EMPTY_BYTES

The ABI encoding of an empty byte array (bytes or string).

RECURSION_LIMIT

The decoder recursion limit. This is currently hardcoded, but may be parameterizable in the future.

Functions

decode

ABI-decodes a token by wrapping it in a single-element tuple.

decode_params

ABI-decodes top-level function args.

decode_sequence

Decodes ABI compliant vector of bytes into vector of tokens described by types param.

encode

ABI-encodes a single token.

encode_params

ABI-encodes a tuple as ABI function params, suitable for passing to a function.

encode_sequence

ABI-encodes a token sequence.