Common Package

Package common provides shared realm utilities for GnoSwap protocol contracts.

Overview

The common package contains helpers that must keep a realm boundary, including GRC20 token operations and native coin validation.

Key Components

1. GRC20 Registry Helpers: Convenient wrappers for GRC20 token operations
2. Coin Utilities: Native coin (GNOT) handling and validation
3. Assertion Utilities: Input validation and authorization checks

API Reference

GRC20 Registry Helpers

The write helpers are crossing adapters and should be called as common.Transfer(cross(cur), ...), common.SafeGRC20Transfer(cross(cur), ...), and so on. They intentionally keep cur realm as the first parameter so the helper runs in common's crossing frame, then forward that live cur to grc20.Teller as Transfer(0, cur, ...). Because GetTokenTeller returns a CallerTeller, the token actor is derived from cur.Previous(), which is the realm that crossed into common. Do not convert these helpers to _ int, rlm realm; that would remove the common crossing boundary and change which realm CallerTeller treats as the actor.

Token Operations:

• GetToken: Retrieves GRC20 token instance
• GetTokenTeller: Gets a CallerTeller for token operations
• IsRegistered: Checks token registration status
• MustRegistered: Validates multiple tokens are registered

Token Queries:

• TotalSupply: Returns total supply of a token
• BalanceOf: Returns token balance for an address
• Allowance: Returns allowance from owner to spender

Token Transfers:

• Transfer/TransferFrom/Approve: Returns error on failure
• SafeGRC20Transfer/SafeGRC20TransferFrom/SafeGRC20Approve: Panics on failure

Coin Utilities

Coin Validation:

• ExistsUserSendCoins: Checks if user sent any coins
• AssertIsNotHandleNativeCoin: Ensures no native coins in transaction