This document discusses different methods for error handling in Solidity including require, assert, revert, and throw. Require checks conditions and reverts state if a condition is not met without consuming gas. Assert prevents bad things from happening and consumes all gas to revert state. Revert reverts state along with an error message. Throw is deprecated and used to revert state.

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S O L I D I T Y
E R R O R H A N D L I N G

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Error Handling
How to do
error handling
in solidity

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Error Handling
require
assert
revert
throw

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require
Here we check the conditions and revert the state in case condition does not met.
This is most commonly used in solidity for error handling
This does not consume any gas
Syntax
require(condition, errorMessage)
Example
require(newBalance > minimumBalance, "Your do not have minimum balance in your account")

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assert
Prevent anything really bad from happening.
This does consume all the gas and revert the state
Syntax
assert(condition)
Example
assert(balance %2 == 0)

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revert
This revert the state along with error message
Syntax
revert("failure reason")
Example
revert("you do not have sufficient balance" )

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throw
This is used to revert the state but this is depreciated now
Syntax
throw
Example
throw;