EIP-4626: Yield Bearing Vault Standard

[AlexTheEntreprenerd]

@joeysantoro

withdraw

function withdraw(address _to, uint256 _value) public returns (uint256 _shares)

Withdraws _value tokens from the vault and transfers them to _to.

MAY return a pro-rata ownership _shares value corresponding to _value, if not MUST return 0.

My criticism of the standard is very simple:
The majority of already existing vault systems use:
withdraw(uint256 shares)

That’s because shares become the unit of measure for the vault once you have deposited.
This is used because:

1. The token takes it’s own meaning and life (bBADGER, yveCRV)
2. The user interface is simpler: “You are going to burn X shares and receive underlying back”
3. The _value math is provenly more complicated, can break (especially if you add fees (e.g. withdrawal fees), and tends to leave dust. This is a known issue by all protocols that use the interface you are recommending.
   To prove this I’ll just search for “Dust” on the Rari Capital Discord:
   
   

Practically this interface causes more issues than necessary, offer sub-par DX and UX and implicitly makes the majority of already existing Vault Systems non-compliant