2

I am hoping someone can help with this. I have been trying to learn smart contracts on Tron with Solidity and tronbox, but I am running into issues when trying to create an ERC721 token.

I have created very simple ERC20.sol contracts using the openzeppelin docs, but get an error for the ERC721 contract found in the openzeppelin docs.

https://docs.openzeppelin.com/contracts/4.x/erc721

TypeError: Member "isContract" not unique after argument-dependent lookup in address.
   --> @openzeppelin/contracts/token/ERC721/ERC721.sol:375:13:
    |
375 |         if (to.isContract()) {
    |             ^^^^^^^^^^^^^
Compilation failed. See above.

I initially thought it might be because of the Solidity version, but I have changed solidity and installed the appropriate openzeppelin version several times and the same error is present for other versions of openzeppelin.

Current setup:

Ubuntu 20.04
tronbox version
Tronbox v2.7.23
Solidity v0.8.0 (tron-solc)
@openzeppelin/contracts  4.2.0
tronbox$ tail -n7  tronbox.js 
    compilers: {
      solc: {
        version: '0.8.0'
      }
    }
  }
}

Full output:

tronbox$  tronbox compile --network development
Compiling ./contracts/GameItem.sol...
Compiling ./contracts/Migrations.sol...
Compiling @openzeppelin/contracts/token/ERC721/ERC721.sol...
Compiling @openzeppelin/contracts/token/ERC721/IERC721.sol...
Compiling @openzeppelin/contracts/token/ERC721/IERC721Receiver.sol...
Compiling @openzeppelin/contracts/token/ERC721/extensions/ERC721URIStorage.sol...
Compiling @openzeppelin/contracts/token/ERC721/extensions/IERC721Metadata.sol...
Compiling @openzeppelin/contracts/utils/Address.sol...
Compiling @openzeppelin/contracts/utils/Context.sol...
Compiling @openzeppelin/contracts/utils/Counters.sol...
Compiling @openzeppelin/contracts/utils/Strings.sol...
Compiling @openzeppelin/contracts/utils/introspection/ERC165.sol...
Compiling @openzeppelin/contracts/utils/introspection/IERC165.sol...

TypeError: Member "isContract" not unique after argument-dependent lookup in address.
   --> @openzeppelin/contracts/token/ERC721/ERC721.sol:375:13:
    |
375 |         if (to.isContract()) {
    |             ^^^^^^^^^^^^^
Compilation failed. See above.
Dale Rodel
  • 21
  • 4

2 Answers2

0

I renamed the Method in Address.sol and ERC721.sol to isContractTron and it Compiled. I do not know if the funcionality is remained!!!!

Philipp Zitzmann
  • 61
  • 6
  • Thank you for your reply. Sorry to report I moved on from Tron to Flow mostly because of transaction fees and redeployable smart contracts. – Dale Rodel Dec 05 '21 at 06:09
0

Tron VM already has Address.isContract (ISCONTRACT) instruction. And the ERC721 contract uses library with another isContract(). Here's my issue for tronbox with an answer from the developer https://github.com/tronprotocol/tronbox/issues/136.

There's a page with TVM/EVM differences: https://developers.tron.network/docs/vm-vs-evm.

Alex Sinyagin
  • 16
  • 3