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      • get user balance & withdraw amount
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      • burn ATokens
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  1. Functions
  2. withdraw

burn ATokens

Previouscollateral checkNextEnsure existing loans are collateralized

Last updated 1 year ago

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Overview

burn ATokens

  • burn calls _burnScaled

Amount of tokens burnt is scaled against current liquidity index

  • amount = 100

  • liquidity index = 1.1

  • amountScaled = 100 / 1.1 = 90

This is to account for interest accrued.

_burnScaled has an interesting approach, in that it looks to mint or burn the difference between unbooked interest accrued and the burn amount.

  • unbooked interest accrued: interest accumulated since last update that has not been minted

If balanceIncrease > amount

  • interest accrued since last update is larger than burn amount

  • mint the difference to the user as aTokens

If balanceIncrease <= amount

  • burn amount exceeds interest accrued

  • burn the difference from the user

If you are confused regarding balanceIncrease and _userState see:

mint
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