Bienvenido a Platzi

Poner especial atención a la primer propiedad de block, ya que esa información irá cambiando a lo largo del tiempo y no siempre seremos capaces de recuperarla (por lo que no deberíamos depender de este dato en particular para alguna operación).

• blockhash(uint blockNumber) returns (bytes32): hash of the given block when blocknumber is one of the 256 most recent blocks; otherwise returns zero
• block.basefee (uint): current block’s base fee (EIP-3198 and EIP-1559)
• block.chainid (uint): current chain id
• block.coinbase (address payable): current block miner’s address
• block.difficulty (uint): current block difficulty
• block.gaslimit (uint): current block gaslimit
• block.number (uint): current block number
• block.timestamp (uint): current block timestamp as seconds since unix epoch
• gasleft() returns (uint256): remaining gas
• msg.data (bytes calldata): complete calldata
• msg.sender (address): sender of the message (current call)
• msg.sig (bytes4): first four bytes of the calldata (i.e. function identifier)
• msg.value (uint): number of wei sent with the message
• tx.gasprice (uint): gas price of the transaction
• tx.origin (address): sender of the transaction (full call chain)