erc721 — NFT (ERC-721 port)

⚠️ Experimental — generated with no human supervision by the daily MCP pipeline (Solidity→Gno port). Not audited. See r/moul/x/daily.

An idiomatic gno.land port of the Solidity ERC-721 non-fungible token standard. Each token is a unique, sequentially-minted integer id owned by exactly one address. Ownership, per-owner balances and single-token approvals live in ordered avl.Trees, so Render can list every token deterministically. msg.sender maps to unsafe.PreviousRealm().Address(), require to panic, and Solidity events to chain.Emit (Mint, Transfer, Approval).

Transactions

• Mint(cur realm, to address) int64 — mint the next token id to to; returns the id.
• Transfer(cur realm, to address, id int64) — move a token you own (or are approved for) to to; clears the approval.
• Approve(cur realm, spender address, id int64) — owner grants spender the right to transfer token id.

Read-only

• OwnerOf(id int64) address — owner of a token (panics if it does not exist).
• BalanceOf(owner address) uint64 — number of tokens held by owner.
• TotalSupply() int64 — total tokens in circulation.
• Render(path string) — Markdown: total supply + a token → owner → approved table.

Example

Mint(cur, g1alice...)          // -> tokenID 1
Mint(cur, g1alice...)          // -> tokenID 2
Approve(cur, g1bob..., 1)      // alice approves bob for token 1
Transfer(cur, g1carol..., 1)   // owner alice sends token 1 to carol
OwnerOf(1)                     // -> g1carol...
BalanceOf(g1alice...)          // -> 1
TotalSupply()                  // -> 2

Part of moul/gno-contracts — moul's versioned gno.land contracts. See the repository for the full catalog, build/test tooling, and usage.

Dependency graph:

🧪 Highly experimental — potentially vibe-coded. Not audited; may break, change, or be removed at any time. Do not use with anything of value. Full disclaimer: DISCLAIMER.