EIP-6789: Rename gas to mana

This EIP suggests renaming gas to mana, as proposed by Vitalik Buterin in 2015

Abstract

This EIP suggests renaming gas to mana, as proposed by Vitalik Buterin in 2015.

Motivation

The underlying motivation for reviving Vitalik’s original proposal from 2015 is that we have finally arrived at the age of Proof-of-Stake, and given the roadmap ahead (i.e. “The Surge”, “The Scourge”, “The Verge”, “The Purge”, and “The Splurge”), I consider this moment as the last opportunity to make such a far-reaching semantic change.

Specification

The key words “MUST”, “MUST NOT”, “REQUIRED”, “SHALL”, “SHALL NOT”, “SHOULD”, “SHOULD NOT”, “RECOMMENDED”, “NOT RECOMMENDED”, “MAY”, and “OPTIONAL” in this document are to be interpreted as described in RFC 2119 and RFC 8174.

The core term gas MUST be renamed to mana.

The following opcodes MUST be renamed:

• GASPRICE to MANAPRICE;
• GASLIMIT to MANALIMIT; and
• GAS to MANA.

Additionally, the input parameters or outputs of the following opcodes MUST be renamed:

• CALL’s gas input parameter to mana;
• CALLCODE’s gas input parameter to mana;
• DELEGATECALL’s gas input parameter to mana;
• STATICCALL’s gas input parameter to mana;
• GASLIMIT’s gasLimit output to manaLimit; and
• GAS’s gas output to mana.

Finally, the following RPC endpoints MUST be renamed:

• eth_estimateGas to eth_estimateMana;
• eth_gasPrice to eth_manaPrice; and
• eth_maxPriorityFeePerGas to eth_maxPriorityFeePerMana.

The description of the RPC endpoints MUST be renamed accordingly:

• eth_estimateMana: Generates and returns an estimate of how much mana is necessary to allow the transaction to complete;
• eth_manaPrice: Returns the current price per mana in wei; and
• eth_maxPriorityFeePerMana: Returns the current maxPriorityFeePerMana per mana in wei.

Rationale

• mana reflects the increased environmental friendliness of Proof-of-Stake;
• mana is generally understood to be ephemeral and non-transferable, which better represents the concept of gas; and
• mana is generally portrayed as renewable, while (natural) gas is non-renewable.

Backwards Compatibility

This proposal is not backward compatible as it renames the core term gas.

Test Cases

Example 1

If a transaction requires more mana than allowed by the manaLimit, it is reverted as an out-of-mana transaction.

Example 2

A Solidity contract to estimate the used mana via the new manaleft() syntax (replacing gasleft()) for dedicated function calls.

// SPDX-License-Identifier: AGPL-3.0
pragma solidity 0.8.19;

contract ManaMetering {
    function oldWay() external view returns (string memory, uint256 manaUsed) {
        string memory hiMom = "Hi Mom, ";
        string memory missYou = "miss you.";
        uint256 startMana = manaleft();
        string memory concat = string(abi.encodePacked(hiMom, missYou));
        manaUsed = startMana - manaleft();
        return (concat, manaUsed);
    }

    function newWay() external view returns (string memory, uint256 manaUsed) {
        string memory hiMom = "Hi Mom, ";
        string memory missYou = "miss you.";
        uint256 startMana = manaleft();
        string memory concat = string.concat(hiMom, missYou);
        manaUsed = startMana - manaleft();
        return (concat, manaUsed);
    }
}

In Vyper, the same behaviour can be replicated with the new transaction property msg.mana, which replaces msg.gas.

Example 3

An example of how to set the manaLimit in MetaMask:

Security Considerations

There are no security considerations directly related to the renaming of gas to mana.

Copyright

Copyright and related rights waived via CC0.

Citation

Please cite this document as:

Pascal Caversaccio (@pcaversaccio), "EIP-6789: Rename gas to mana [DRAFT]," Ethereum Improvement Proposals, no. 6789, March 2023. [Online serial]. Available: https://eips.ethereum.org/EIPS/eip-6789.