Change the bridges function's visibility to external

[Zena-park]

Since the bridges function has no internal calls, it is appropriate to modify public to external.

• bridgeETH https://github.com/tokamak-network/tokamak-thanos/blob/5ad9baac98217a0c1533969b00076d9a4443edba/packages/tokamak/contracts-bedrock/src/universal/StandardBridge.sol#L214-L215

 function bridgeETH(uint256 _amount, uint32 _minGasLimit, bytes calldata _extraData) external payable onlyEOA { 

• bridgeETHTo https://github.com/tokamak-network/tokamak-thanos/blob/5ad9baac98217a0c1533969b00076d9a4443edba/packages/tokamak/contracts-bedrock/src/universal/StandardBridge.sol#L230-L231

function bridgeETHTo(address _to, uint256 _amount, uint32 _minGasLimit, bytes calldata _extraData) external payable {

• bridgeERC20 https://github.com/tokamak-network/tokamak-thanos/blob/5ad9baac98217a0c1533969b00076d9a4443edba/packages/tokamak/contracts-bedrock/src/universal/StandardBridge.sol#L245-L254

function bridgeERC20(
        address _localToken,
        address _remoteToken,
        uint256 _amount,
        uint32 _minGasLimit,
        bytes calldata _extraData
    )
        external
        onlyEOA
    {

• bridgeERC20To https://github.com/tokamak-network/tokamak-thanos/blob/5ad9baac98217a0c1533969b00076d9a4443edba/packages/tokamak/contracts-bedrock/src/universal/StandardBridge.sol#L270-L279

 function bridgeERC20To(
        address _localToken,
        address _remoteToken,
        address _to,
        uint256 _amount,
        uint32 _minGasLimit,
        bytes calldata _extraData
    )
        external
    {

[nguyenzung]

Hi @Zena-park

I think we should keep it. There are 2 reasons

• public function can give us better gas cost than external function
• Optimism uses public for bridging functions

[Zena-park]

I don't think there will be much difference in gas.

However, I think it is better to use external when using it only in external calls according to the basic grammar.

Anyway, it is just a difference of opinion, not an error, so I will close the issue.