📝 update SNIP-3 new syntax

SNIPS/snip-3.md

@@ -16,28 +16,28 @@ Inspired by [EIP-721](https://eips.ethereum.org/EIPS/eip-721).
 
 ## Abstract
 
-See https://eips.ethereum.org/EIPS/eip-721#abstract.
+See <https://eips.ethereum.org/EIPS/eip-721#abstract>.
 
 ## Motivation
 
-See https://eips.ethereum.org/EIPS/eip-721#motivation.
+See <https://eips.ethereum.org/EIPS/eip-721#motivation>.
 
 ## Specification
 
 ### Methods
 
 **NOTES**:
- - The following specifications use syntax from Cairo `0.8.1` (or above)
+
+- The following specifications use syntax from Cairo `2.9.2` (or above)
 
 ### balanceOf
 
 Count all NFTs assigned to an owner.
 
 NFTs assigned to the zero address are considered invalid, and this function throws for queries about the zero address.
 
-``` cairo
-    func balanceOf(owner: felt) -> (balance: Uint256):
-    end
+```cairo
+fn balanceOf(self: @TState, account: ContractAddress) -> u256
 ```
 
 ### ownerOf
@@ -46,9 +46,8 @@ Find the owner of an NFT.
 
 NFTs assigned to zero address are considered invalid, and queries about them do throw.
 
-``` cairo
-    func ownerOf(tokenId: Uint256) -> (owner: felt):
-    end
+```cairo
+fn ownerOf(self: @TState, tokenId: u256) -> ContractAddress
 ```
 
 ### safeTransferFrom
@@ -57,89 +56,103 @@ Transfers the ownership of an NFT from one address to another address.
 
 Throws unless `get_caller_address` is the current owner, an authorized operator, or the approved address for this NFT.
 
-Throws if `from_` is not the current owner.
-
-``` cairo
-    func safeTransferFrom(
-            from_: felt, 
-            to: felt, 
-            tokenId: Uint256, 
-            data_len: felt,
-            data: felt*
-        ):
-    end
+Throws if `from` is not the current owner.
+
+```cairo
+fn safeTransferFrom(
+    ref self: TState,
+    from: ContractAddress,
+    to: ContractAddress,
+    tokenId: u256,
+    data: Span<felt252>
+)
 ```
 
 ### transferFrom
 
-``` cairo
-    func transferFrom(from_: felt, to: felt, tokenId: Uint256):
-    end
+```cairo
+fn transferFrom(ref self: TState, from: ContractAddress, to: ContractAddress, tokenId: u256)
 ```
 
 ### approve
 
-``` cairo
-    func approve(approved: felt, tokenId: Uint256):
-    end
+```cairo
+fn approve(ref self: TState, approved: ContractAddress, tokenId: u256)
 ```
 
 ### setApprovalForAll
 
-``` cairo
-    func setApprovalForAll(operator: felt, approved: felt):
-    end
+```cairo
+fn setApprovalForAll(ref self: TState, operator: ContractAddress, approved: bool)
 ```
 
 ### getApproved
 
-``` cairo
-    func getApproved(tokenId: Uint256) -> (approved: felt):
-    end
+```cairo
+fn getApproved(self: @TState, tokenId: u256) -> ContractAddress
 ```
 
 ### isApprovedForAll
 
-``` cairo
-    func isApprovedForAll(owner: felt, operator: felt) -> (isApproved: felt):
-    end
+```cairo
+fn isApprovedForAll(self: @TState, owner: ContractAddress, operator: ContractAddress) -> bool
 ```
 
 ### Events
 
 #### Transfer
 
-``` cairo
-    @event
-    func Transfer(from_: felt, to: felt, tokenId: Uint256):
-    end
+```cairo
+/// Emitted when `token_id` token is transferred from `from` to `to`.
+#[derive(Drop, PartialEq, starknet::Event)]
+struct Transfer {
+    #[key]
+    from: ContractAddress,
+    #[key]
+    to: ContractAddress,
+    #[key]
+    token_id: u256,
+}
 ```
 
 #### Approval
 
-``` cairo
-    @event
-    func Approval(owner: felt, approved: felt, tokenId: Uint256):
-    end
+```cairo
+/// Emitted when `owner` enables `approved` to manage the `token_id` token.
+#[derive(Drop, PartialEq, starknet::Event)]
+struct Approval {
+    #[key]
+    owner: ContractAddress,
+    #[key]
+    approved: ContractAddress,
+    #[key]
+    token_id: u256,
+}
 ```
 
 #### ApprovalForAll
 
-``` cairo
-    @event
-    func ApprovalForAll(owner: felt, operator: felt, approved: felt):
-    end
+```cairo
+/// Emitted when `owner` enables or disables (`approved`) `operator` to manage
+/// all of its assets.
+#[derive(Drop, PartialEq, starknet::Event)]
+struct ApprovalForAll {
+    #[key]
+    owner: ContractAddress,
+    #[key]
+    operator: ContractAddress,
+    approved: bool,
+}
 ```
 
 ## Implementation
 
-#### Example implementations are available at
-- [OpenZeppelin implementation](https://github.com/OpenZeppelin/cairo-contracts/tree/main/src/openzeppelin/token/erc721)
+Example implementations are available at
 
+- [OpenZeppelin implementation](https://github.com/OpenZeppelin/cairo-contracts/blob/main/packages/token/src/erc721/erc721.cairo)
 
 ## History
 
-
 ## Copyright
 
-Copyright and related rights waived via [MIT](../LICENSE).
+Copyright and related rights waived via [MIT](../LICENSE).