What is 210_000 in " uint256 internal constant FUNDS_SEND_GAS_LIMIT = 210_000;"?

Question

I've never seen this type syntax in solidity? Can someone please let me know what is it and why is it written in that way?

Source : https://github.com/ourzora/zora-drops-contracts/blob/8755992e3ba55c9c9d1b061dacbe76278a225f83/src/ERC721Drop.sol#L61

Answer 1

It's just a variable. We can write this like:

uint fundsSendGasLimit = 210000;

There is nothing "too" much different. But of course there are some visibility and mutability factors.

Lastly, you can use _ as a separator. Solidity compiler will understand what is for. 1_000_000 equals 1000000 etc