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This document is better viewed at https://docs.openzeppelin.com/contracts/api/metatx

Core

ERC2771Context 

import "@openzeppelin/contracts/metatx/ERC2771Context.sol";

Context variant with ERC2771 support.

The usage of delegatecall in this contract is dangerous and may result in context corruption. Any forwarded request to this contract triggering a delegatecall to itself will result in an invalid _msgSender recovery.
Functions

constructor(address trustedForwarder) internal

isTrustedForwarder(address forwarder) → bool public

_msgSender() → address internal

_msgData() → bytes internal

_contextSuffixLength() → uint256 internal

ERC-2771 specifies the context as being a single address (20 bytes).

Utils

MinimalForwarder 

import "@openzeppelin/contracts/metatx/MinimalForwarder.sol";

Simple minimal forwarder to be used together with an ERC2771 compatible contract. See ERC2771Context.

MinimalForwarder is mainly meant for testing, as it is missing features to be a good production-ready forwarder. This contract does not intend to have all the properties that are needed for a sound forwarding system. A fully functioning forwarding system with good properties requires more complexity. We suggest you look at other projects such as the GSN which do have the goal of building a system like that.

Functions
EIP712
Events
IERC5267

constructor() public

getNonce(address from) → uint256 public

verify(struct MinimalForwarder.ForwardRequest req, bytes signature) → bool public

execute(struct MinimalForwarder.ForwardRequest req, bytes signature) → bool, bytes public

← Interfaces
Proxy →