LPFeeLibrary
Library of helper functions for a pools LP fee
State Variables
DYNAMIC_FEE_FLAG
An lp fee of exactly 0b1000000... signals a dynamic fee pool. This isn't a valid static fee as it is > MAX_LP_FEE
uint24 public constant DYNAMIC_FEE_FLAG = 0x800000;
OVERRIDE_FEE_FLAG
the second bit of the fee returned by beforeSwap is used to signal if the stored LP fee should be overridden in this swap
uint24 public constant OVERRIDE_FEE_FLAG = 0x400000;
REMOVE_OVERRIDE_MASK
mask to remove the override fee flag from a fee returned by the beforeSwaphook
uint24 public constant REMOVE_OVERRIDE_MASK = 0xBFFFFF;
MAX_LP_FEE
the lp fee is represented in hundredths of a bip, so the max is 100%
uint24 public constant MAX_LP_FEE = 1000000;
Functions
isDynamicFee
returns true if a pool's LP fee signals that the pool has a dynamic fee
function isDynamicFee(uint24 self) internal pure returns (bool);
Parameters
| Name | Type | Description |
|---|---|---|
self | uint24 | The fee to check |
Returns
| Name | Type | Description |
|---|---|---|
<none> | bool | bool True of the fee is dynamic |
isValid
returns true if an LP fee is valid, aka not above the maximum permitted fee
function isValid(uint24 self) internal pure returns (bool);
Parameters
| Name | Type | Description |
|---|---|---|
self | uint24 | The fee to check |
Returns
| Name | Type | Description |
|---|---|---|
<none> | bool | bool True of the fee is valid |
validate
validates whether an LP fee is larger than the maximum, and reverts if invalid
function validate(uint24 self) internal pure;
Parameters
| Name | Type | Description |
|---|---|---|
self | uint24 | The fee to validate |
getInitialLPFee
gets and validates the initial LP fee for a pool. Dynamic fee pools have an initial fee of 0.
if a dynamic fee pool wants a non-0 initial fee, it should call updateDynamicLPFee in the afterInitialize hook
function getInitialLPFee(uint24 self) internal pure returns (uint24);
Parameters
| Name | Type | Description |
|---|---|---|
self | uint24 | The fee to get the initial LP from |
Returns
| Name | Type | Description |
|---|---|---|
<none> | uint24 | initialFee 0 if the fee is dynamic, otherwise the fee (if valid) |
isOverride
returns true if the fee has the override flag set (2nd highest bit of the uint24)
function isOverride(uint24 self) internal pure returns (bool);
Parameters
| Name | Type | Description |
|---|---|---|
self | uint24 | The fee to check |
Returns
| Name | Type | Description |
|---|---|---|
<none> | bool | bool True of the fee has the override flag set |
removeOverrideFlag
returns a fee with the override flag removed
function removeOverrideFlag(uint24 self) internal pure returns (uint24);
Parameters
| Name | Type | Description |
|---|---|---|
self | uint24 | The fee to remove the override flag from |
Returns
| Name | Type | Description |
|---|---|---|
<none> | uint24 | fee The fee without the override flag set |
removeOverrideFlagAndValidate
Removes the override flag and validates the fee (reverts if the fee is too large)
function removeOverrideFlagAndValidate(uint24 self) internal pure returns (uint24 fee);
Parameters
| Name | Type | Description |
|---|---|---|
self | uint24 | The fee to remove the override flag from, and then validate |
Returns
| Name | Type | Description |
|---|---|---|
fee | uint24 | The fee without the override flag set (if valid) |
Errors
LPFeeTooLarge
Thrown when the static or dynamic fee on a pool exceeds 100%.
error LPFeeTooLarge(uint24 fee);