Use of Deprecated Functions

As time goes by, functions and operators in Solidity are deprecated and often replaced. It's important to not use deprecated functions, as it can lead to unexpected effects and compilation errors.

Here is a non-exhaustive list of deprecated functions and alternatives. Many alternatives are simply aliases, and won't break current behaviour if used as a replacement for its deprecated counterpart.

DeprecatedAlternatives
suicide(address)/selfdestruct(address)N/A
block.blockhash(uint)blockhash(uint)
sha3(...)keccak256(...)
callcode(...)delegatecall(...)
throwrevert()
msg.gasgasleft
constantview
varcorresponding type name

Sources