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Loupe

The Loupe module is entirely read-only. It provides the introspection functions required by EIP-2535, allowing block explorers, frontends, and indexing bots to "see" inside the Garden and map out its capabilities.

DiamondLoupeBase.sol & DiamondLoupeFacet.sol​

These contracts implement the standard IDiamondLoupe interface. Because a Garden's capabilities can change over time (via upgrades), UIs should use these functions to verify if a Garden supports a specific action before sending a transaction.

It also implements IERC165, allowing other contracts to query supportsInterface(bytes4).

Key Introspection Functions for Builders:

  • facets(): Returns all active facet addresses and their bundled function selectors.
  • facetFunctionSelectors(address _facet): Returns all functions bundled in a specific facet.
  • facetAddress(bytes4 _functionSelector): Returns the exact facet address handling a specific function.

Crucial Snippet: Querying a Selector

Builders can use this to dynamically check if a Garden has a specific feature installed:

// From DiamondLoupeBase.sol
/// @notice Retrieves the facet that supports the given function selector
function _facetAddress(bytes4 _functionSelector) internal view returns (address facetAddress_) {
    // Looks up the specific routing mapping in Diamond Storage
    facetAddress_ = DiamondCutStorage.layout().selectorToFacetAndPosition[_functionSelector].facetAddress;
}

DiamondLoupeStorage.sol​

Stores the mappings for ERC-165 interface detection (mapping(bytes4 => bool) supportedInterfaces). This is initialized when the Garden is first deployed.